As Filed with the Securities and Exchange Commission on February 6, 2002

                                                    Registration No. 333-______

================================================================================

                       SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 20549

                                    FORM S-3
             REGISTRATION STATEMENT UNDER THE SECURITIES ACT OF 1933


                                                                                  
           KeySpan Corporation                               New York                               11-3431358
           KeySpan Trust I                                   Delaware                               11-6563698
           KeySpan Trust II                                  Delaware                               11-3622443
           KeySpan Trust III                                 Delaware                               11-6563239

 (Exact Name of Registrant as Specified in       (State or Other Jurisdiction of         (I.R.S. Employer Identification
               its Charter)                       Incorporation or Organization)                     Number)


                            Steven L. Zelkowitz, Esq.
                 One MetroTech Center, Brooklyn, New York 11201
              175 East Old Country Road, Hicksville, New York 11801
                            (718) 403-1000 (Brooklyn)
                           (516) 755-6650 (Hicksville)
               (Address, including zip code, and telephone number,
            including area code, of registrant's principal executive
                         offices and agent for service)

                                    Copy to:
                             Raymond W. Wagner, Esq.
                           Simpson Thacher & Bartlett
                              425 Lexington Avenue
                          New York, New York 10017-3954

                     -------------------------------------

         Approximate date of commencement of proposed sale to public: From time
to time after this Registration Statement becomes effective as determined by
market conditions.

         If the only securities being registered on this form are being offered
pursuant to dividend or interest reinvestment plans, please check the following
box. / /

         If any of the securities being registered on this form are to be
offered on a delayed or continuous basis pursuant to Rule 415 under the
Securities Act of 1933, other than securities offered only in connection with
dividend or interest reinvestment plans, check the following box. /X/

         If this form is filed to register additional securities for an offering
pursuant to Rule 462(b) under the Securities Act, please check the following box
and list the Securities Act registration statement number of the earlier
effective registration statement for the same offering. / /

         If this form is a post-effective amendment filed pursuant to Rule
462(c) under the Securities Act, check the following box and list the Securities
Act registration statement number of the earlier effective registration
statement for the same offering. / /

         If delivery of the prospectus is expected to be made pursuant to Rule
434, please check the following box. / /

                    ----------------------------------------

                         CALCULATION OF REGISTRATION FEE
                              (See following page)

                  --------------------------------------------

         The Registrants hereby amend this Registration Statement on such date
or dates as may be necessary to delay its effective date until the Registrants
shall file a further amendment which specifically states that this Registration
Statement shall thereafter become effective in accordance with Section 8(a) of
the Securities Act or until this Registration Statement shall become effective
on such date as the Securities and Exchange Commission, acting pursuant to said
Section 8(a), may determine.









                         CALCULATION OF REGISTRATION FEE

====================================================================================================================================
                                                                                                        
                                                                         Proposed Maximum
            Title of Each Class of                                      Aggregate Offering       Proposed Maximum        Amount of
               Securities to be                     Amount to be             Price Per          Aggregate Offering     Registration
                  Registered                       Registered (1)          Security (2)          Price (3)(4)(5)          Fee(1)
- ------------------------------------------------------------------------------------------------------------------------------------
Debt Securities of KeySpan Corporation (5).
- -----------------------------------------------
Trust Preferred Securities of the Trusts (6)
- -----------------------------------------------
Guarantees of Trust Preferred Securities of
    the Trusts and certain back-up
    obligations (7)........................
- -----------------------------------------------
Preferred Stock, par value $.01 per share, of
    KeySpan Corporation (8)................
- -----------------------------------------------
Depositary Shares (9)......................
- -----------------------------------------------
Common Stock, par value $.01 per share, of
    KeySpan Corporation (10)...............
- -----------------------------------------------
Rights to purchase Series D Preferred Stock,
    par value $.01 per share, of KeySpan
    Corporation  (11)......................
- -----------------------------------------------
Stock Purchase Contracts of KeySpan
    Corporation (12).......................
- -----------------------------------------------
Stock Purchase Units (13)..................
- -----------------------------------------------
Warrants of KeySpan
    Corporation (14).......................
- -----------------------------------------------
Warrant Units (15).........................
- -----------------------------------------------
    Total..................................        $1,200,000,000                                 $1,200,000,000         $110,400
====================================================================================================================================

(1)      Pursuant to General Instruction II.D to Form S-3, the Amount to be
         Registered, Proposed Maximum Aggregate Offering Price Per Security and
         Proposed Maximum Aggregate Offering Price has been omitted for each
         class of securities that is registered hereby.

(2)      The Proposed Maximum Aggregate Offering Price Per Security will be
         determined from time to time by the relevant Registrant in connection
         with the issuance by that Registrant of the securities registered
         hereunder.

(3)      The Proposed Maximum Aggregate Offering Price has been estimated solely
         for purposes of calculating the registration fee pursuant to Rule
         457(o) under the Securities Act of 1933 and reflects the maximum
         offering price of securities issued, rather than the principal amount
         of securities that may be issued at a discount and shall not exceed
         $1,200,000,000 or the equivalent thereof, based on the exchange rate on
         the applicable offering date, in one or more currencies or currency
         units identified by the applicable Registrant at the time of offering.

(4)      Excluding accrued interest, distributions and dividends, if any.

(5)      An indeterminate number of debt securities of KeySpan Corporation are
         covered by this registration statement. Debt securities may be issued
         (a) separately, (b) as part of stock purchase units or warrant units
         which are registered hereby or (c) upon exercise of warrants to
         purchase debt securities which are registered hereby.

(6)      An indeterminate number of trust preferred securities of KeySpan Trust
         I, KeySpan Trust II and KeySpan Trust III (each a "Trust") are covered
         by this registration statement. Trust preferred securities may be
         issued separately or as part of stock purchase units or warrant units
         which are registered hereby. Debt securities of KeySpan may be issued
         to any Trust in exchange for trust preferred securities, in which event
         such debt securities may later be distributed to the holders of trust
         preferred securities upon a dissolution of such Trust and the
         distribution of the assets thereof.

(7)      Includes the rights of holders of the trust preferred securities under
         any guarantees and certain back-up undertakings, comprised of the
         obligations of KeySpan Corporation, to provide certain indemnities in
         respect of, and pay and be responsible for certain costs, expenses,
         debts and liabilities of, each Trust (other than with respect to the
         trust preferred securities) and such obligations of KeySpan Corporation
         as set forth in the amended and restated declaration of trust of each
         Trust and the related indenture, in each case as further described in
         the registration statement. The guarantees, when taken together with
         KeySpan Corporation's obligations under the debt securities, the
         related indenture and the amended and restated declaration of trust,
         will provide a full and unconditional guarantee by KeySpan Corporation
         of payments due on the trust preferred securities. No separate
         consideration will be received for any guarantees or such back-up
         obligations.

(8)      An indeterminate number of shares of preferred stock of KeySpan
         Corporation are covered by this registration statement. Preferred stock
         may be issued (a) separately, (b) as part of stock purchase units which
         are registered hereby or (c) upon exercise of warrants to purchase
         preferred stock which are registered hereby.

(9)      An indeterminate number of depositary shares, representing fractional
         interests in the preferred stock of KeySpan Corporation, are covered by
         this registration statement. In the event KeySpan Corporation elects to
         offer to the public such fractional interests, the depositary shares
         will be issued to a depositary under a deposit agreement. Depositary
         shares may be issued (a) separately, (b) as part of stock purchase
         units or warrant units which are registered hereby or (c) upon exercise
         of warrants to purchase depositary shares which are registered hereby.

(10)     An indeterminate number of shares of common stock, par value $.01 per
         share of KeySpan Corporation are covered by this registration
         statement. Common stock may be issued (a) separately, (b) upon the
         conversion of either the debt securities or the shares of preferred
         stock of KeySpan Corporation, or trust preferred securities of a Trust,
         each of which are registered hereby, (c) upon settlement of stock
         purchase contracts of KeySpan Corporation or stock purchase units, each
         of which are registered hereby or (d) upon exercise of warrants to
         purchase common stock which are registered hereby. Shares of common
         stock issued upon conversion of debt securities, preferred stock or
         trust preferred securities will be issued without the payment of
         additional consideration.

(11)     An indeterminate number of rights to purchase Series D Preferred Stock,
         par value $0.01 per share, of KeySpan Corporation (the "Rights"), are
         covered by this registration statement. Prior to the occurrence of
         certain events, the Rights will not be exercisable or evidenced
         separately from shares of common stock of KeySpan Corporation. The
         value, if any, attributable to those Rights is reflected in the market
         price of the common stock.

(12)     An indeterminate number of stock purchase contracts of KeySpan
         Corporation are covered by this registration statement. Each stock
         purchase contract may be issued separately or as part of a stock
         purchase unit. A stock purchase contract obligates the holder, upon
         settlement, to purchase an indeterminate number of shares of common
         stock of KeySpan Corporation. If a stock purchase contract is issued as
         part of a stock purchase unit, no separate consideration will be
         received for the stock purchase contract.

(13)     An indeterminate number of stock purchase units are covered by this
         registration statement. Each stock purchase unit consists of (a) a
         stock purchase contract, under which the holder, upon settlement, will
         purchase an indeterminate number of shares of common stock of KeySpan
         Corporation and attached Rights and (b) a debt security of KeySpan
         Corporation, a share of preferred stock of KeySpan Corporation or a
         depositary share relating to that preferred stock, a trust preferred
         security of a Trust or a debt obligation of a third party, including a
         U.S. Treasury security. Each debt security, share of preferred stock or
         depositary share relating to preferred stock or debt obligation of a
         third party may be pledged to secure the obligation of the holder to
         purchase common stock.

(14)     An indeterminate number of warrants, representing rights to purchase
         preferred stock, depositary shares, common stock or debt securities of
         KeySpan Corporation, each of which is registered hereby, are covered by
         this registration statement.

(15)     An indeterminate number of warrant units are covered by this
         registration statement. Each warrant unit consists of (a) a warrant
         under which the holder, upon exercise, will purchase an indeterminate
         number of shares of common stock of KeySpan Corporation and (b) a debt
         security of KeySpan Corporation, a share of preferred stock of KeySpan
         Corporation or depositary shares relating to that preferred stock, or a
         trust preferred security of a Trust.

         As permitted by Rule 429 under the Securities Act of 1933, the
prospectus included herein is a combined prospectus which also relates to the
same classes of securities of the Registrants previously registered under the
Registration Statement on Form S-3 (No. 333-60294) of the Registrants. A filing
fee of $125,000 was paid in connection with $500,000,000 of securities that
remain eligible to be sold under such Registration Statement. This registration
statement constitutes Post-Effective Amendment No. 1 to Registration Statement
No. 333-60294, which shall become effective concurrently with this registration
statement in accordance with 8(c) of the Securities Act.


================================================================================


The  information in this  prospectus is not complete and may be changed.  We may
not sell  these  securities  until the  registration  statement  filed  with the
Securities and Exchange Commission is effective. This prospectus is not an offer
to  sell  these  securities  and it is not  soliciting  an  offer  to buy  these
securities in any state where the offer or sale is not permitted.




                  SUBJECT TO COMPLETION, DATED FEBRUARY 6, 2002


                                   PROSPECTUS

                                     [LOGO]


                               KEYSPAN CORPORATION

                                 $1,700,000,000

                                 Debt Securities
                                 Preferred Stock
                                Depositary Shares
                                  Common Stock
                              Stock Purchase Units
                            Stock Purchase Contracts
                                    Warrants
                                  Warrant Units

                                 KEYSPAN TRUST I
                                KEYSPAN TRUST II
                                KEYSPAN TRUST III

                           Trust Preferred Securities

                 Guaranteed, to the extent set forth herein, by
                               KEYSPAN CORPORATION

         KeySpan Corporation will provide the specific terms of these securities
in supplements to this prospectus. You should read this prospectus and the
applicable prospectus supplement carefully before you invest.

         Neither the Securities and Exchange Commission nor any state securities
commission has approved or disapproved these securities or determined if this
prospectus is truthful or complete. Any representation to the contrary is a
criminal offense.

                 The date of this prospectus is ________, 2002.









                                TABLE OF CONTENTS

                                                                                                         Page
                                                                                                               
About This Prospectus...............................................................................................i
- ---------------------
Risk Factors........................................................................................................1
- ------------
Forward-Looking Statements..........................................................................................3
- --------------------------
Keyspan Corporation.................................................................................................4
- -------------------
The Trusts..........................................................................................................5
- ----------
Use of Proceeds.....................................................................................................5
- ---------------
Ratio of Earnings to Fixed Charges and of Earnings to Combined Fixed Charges and Preferred Stock
- -------------------------------------------------------------------------------------------------
     Dividends......................................................................................................5
     ---------
Description of Debt Securities......................................................................................7
- ------------------------------
Description of Preferred Stock.....................................................................................21
- ------------------------------
Description of Depositary Shares...................................................................................24
- --------------------------------
Description of the Trust Preferred Securities......................................................................27
- ---------------------------------------------
Description of Common Stock........................................................................................39
- ---------------------------
Description of Stock Purchase Contracts and Stock Purchase Units...................................................43
- ----------------------------------------------------------------
Description of Warrants and Warrant Units..........................................................................44
- -----------------------------------------
United States Federal Income Tax Consequences......................................................................46
- ---------------------------------------------
ERISA Considerations...............................................................................................64
- --------------------
Plan of Distribution...............................................................................................68
- --------------------
Legal Opinions.....................................................................................................69
- --------------
Experts............................................................................................................69
- -------
Where You Can Find More Information................................................................................70
- -----------------------------------


                              About This Prospectus


         As used in this prospectus and any prospectus supplement or term sheet,
"KeySpan" generally means KeySpan Corporation, together with its consolidated
subsidiaries. However, in the descriptions of the securities offered in this
prospectus and related risk factors, "KeySpan" means KeySpan Corporation and not
any of its subsidiaries.

         You should rely only on the information incorporated by reference or
provided in this prospectus or any supplement or term sheet. KeySpan has not
authorized anyone else to provide you with different information. KeySpan is not
making an offer of these securities in any state where the offer is not
permitted. You should not assume that the information in this prospectus or any
supplement is accurate as of any date other than the date on the front of these
documents.








                                  Risk Factors


         In addition to the risk factors discussed below relating to trust
preferred securities, if appropriate, we will include risk factors relating to
securities offered using this prospectus in the prospectus supplement relating
to the offered securities.

Risk Factors Relating to the Trust Preferred Securities

         Your investment in the trust preferred securities will involve several
risks. You should carefully consider the following discussion of risks, and the
other information in this prospectus, before deciding whether an investment in
the trust preferred securities is suitable for you.

      KeySpan is not required to pay you under the guarantee and the
      subordinated debt securities unless it first makes other required
      payments.

         KeySpan's obligations under the subordinated debt securities will rank
junior to all of its senior debt. This means that KeySpan cannot make any
payments on the subordinated debt securities if it defaults on a payment of
senior debt and does not cure the default within the applicable grace period or
if the senior debt becomes immediately due because of a default and has not yet
been paid in full. In addition, KeySpan's obligations under the subordinated
debt securities will be effectively subordinated to all of the existing and
future liabilities of its subsidiaries. KeySpan's obligations under the
guarantee are subordinated to all of its other liabilities. This means that
KeySpan cannot make any payments on the guarantee if it defaults on a payment on
any of its other liabilities. In addition, in the event of the bankruptcy,
liquidation or dissolution of KeySpan, its assets would be available to pay
obligations under the guarantee only after it has made all payments on its other
liabilities.

         Neither the trust preferred securities, the subordinated debt
securities nor the guarantee limit KeySpan's ability to incur additional
indebtedness, including indebtedness that ranks senior in priority of payment to
the subordinated debt securities and the guarantee.

      KeySpan is not required to pay you under the guarantee if the relevant
trust does not have cash available.

         The ability of each trust to make payments on the trust preferred
securities is solely dependent upon KeySpan making the related payments on the
subordinated debt securities when due.

         If KeySpan defaults on its obligations to make payments on the
subordinated debt securities, the trusts will not have sufficient funds to make
payments on the trust preferred securities. In those circumstances, you will not
be able to rely upon the guarantee for payment of these amounts.

      Deferral of distributions would have adverse tax consequences for you and
      may adversely affect the trading price of the trust preferred securities.

         If distributions on the trust preferred securities are deferred, you
will be required to recognize interest income for United States federal income
tax purposes in respect of your ratable share of the interest on the
subordinated debt securities held by the trust before you receive any cash
distributions relating to this interest. In addition, you will not receive this
cash if you sold the trust preferred securities before the end of any deferral
period or before the record date relating to distributions which are paid.

         KeySpan has no current intention of deferring interest payments on the
subordinated debt securities and believes that such deferral is a remote
possibility. However, if KeySpan exercises its right to do so in the future, the
trust preferred securities may trade at prices that do not fully reflect the
value of accrued but unpaid interest on the subordinated debt securities. If you
sell the trust preferred securities during an interest deferral period, you may
not receive the same return on investment as someone else who continues to hold
the trust preferred securities. In addition, the existence of KeySpan's right to
defer payments of interest on the subordinated debt securities may mean that the
market price for the trust preferred securities, which represent an undivided
beneficial interest in the subordinated debt securities, may be more volatile
than other securities that do not have these rights.

      You should not rely on the distributions from the trust preferred
      securities through their maturity date--they may be redeemed at any time
      if specified changes in tax or investment company law occur.

         If specified changes in tax or investment company law occur and other
specified conditions are satisfied, the trust preferred securities could be
redeemed by the trusts at a redemption price equal to their issue price plus any
accrued and unpaid distributions.

      You should not rely on the distributions from the trust preferred
      securities through their maturity date--they may be redeemed at KeySpan's
      option.

         The trust preferred securities may be redeemed in whole, at any time,
or in part, from time to time, at a redemption price equal to their issue price
plus any accrued and unpaid distributions. You should assume that this
redemption option will be exercised if KeySpan is able to refinance at a lower
interest rate or it is otherwise in its interest to redeem the subordinated debt
securities. If KeySpan redeems the subordinated debt securities, the trusts must
redeem the trust preferred securities in an aggregate liquidation amount equal
to the aggregate principal amount of subordinated debt securities redeemed.

      You may suffer a loss if subordinated debt securities are distributed to
      you in exchange for preferred securities because market prices for the
      preferred securities and the subordinated debt securities may not be
      equal.

         KeySpan cannot give you any assurance as to the market prices for the
preferred securities or the subordinated debt securities that may be distributed
in exchange for preferred securities. Accordingly, the preferred securities that
an investor may purchase, whether pursuant to the offer made by this prospectus
or in the secondary market, or the subordinated debt securities that a holder of
preferred securities may receive in exchange for preferred securities, may trade
at a discount to the price that the investor paid to purchase the preferred
securities.

      You could suffer adverse tax consequences if KeySpan terminates the trusts
      and distributes the subordinated debt securities to holders.

         KeySpan has the right to terminate the trust at any time. If KeySpan
decides to exercise this right, the trust will redeem the trust preferred
securities by distributing subordinated debt securities to holders of the trust
preferred securities on a proportionate basis.

         Under current United States federal income tax law, a distribution of
subordinated debt securities to you on the dissolution of the trust should not
be a taxable event to you. However, if the trust is characterized for United
States federal income tax purposes as an association taxable as a corporation at
the time it is dissolved or if there is a change in law, the distribution of
subordinated debt securities to you may be a taxable event to you.

      Possible tax law changes may affect the trust preferred securities.

         On January 24, 2002, legislation was proposed that generally would deny
the interest deduction for interest paid or accrued on debt instruments that are
not included as liabilities in the certified annual report of the issuer. If
this provision were to apply to the subordinated debt securities, KeySpan would
not be able to deduct interest payments on the subordinated debt securities.
This provision is proposed to be effective for instruments issued on or after
the date of enactment of such legislation. There can be no assurance that the
proposed legislation, future legislative proposals or any final legislation will
not adversely affect the ability of KeySpan to deduct interest on the
subordinated debt securities or otherwise affect the tax treatment of KeySpan or
the investors in the trust preferred securities as described in this
registration statement. Such a change could give rise to a tax event, which
would permit KeySpan to redeem the subordinated debt securities. Such redemption
would cause a mandatory redemption of the trust preferred securities and would
constitute a taxable event as described under "United States Federal Income Tax
Consequences--Trust preferred securities--Consequences to United States
holders--Sales of trust preferred securities or redemption of subordinated debt
securities." See also "Description of the Trust Preferred Securities--Special
event redemption" in this registration statement.

      Because you have limited voting rights, you may not be able to prevent the
      trusts from taking actions you may not agree with.

         You will have limited voting rights. In particular, except for the
limited exceptions described below, only KeySpan can elect or remove any of the
trustees.

                           Forward-Looking Statements


         Some of the information included in this prospectus, any prospectus
supplement or term sheet and the documents KeySpan has incorporated by reference
contain forward-looking statements within the meaning of the Private Securities
Litigation Reform Act of 1995, as amended. Such statements relate to future
events or KeySpan's future financial performance. KeySpan uses words such as
"anticipate," "believe," "expect," "may," "project," "will" or other similar
words to identify forward-looking statements.

         Without limiting the foregoing, all statements relating to KeySpan's

          -    future outlook,

          -    anticipated capital expenditures,

          -    future cash flows and borrowings,

          -    pursuit of potential future acquisition opportunities, and

          -    sources of funding

are forward-looking statements. These forward-looking statements are based on
numerous assumptions that KeySpan believes are reasonable, but they are open to
a wide range of uncertainties and business risks and actual results may differ
materially from those discussed in these statements.

         Among the factors that could cause actual results to differ materially
are:

          -    general economic  conditions,  especially in the Northeast United
               States;

          -    available sources and costs of fuel;

          -    volatility of energy prices in a deregulated  market  environment
               as well as in the source of natural gas and fuel used to generate
               electricity;

          -    potential  write-down of our investment in natural gas properties
               when natural gas prices are  depressed or if we have  significant
               downward revisions in our estimated proved gas reserves;

          -    federal   and  state   regulatory   initiatives   that   increase
               competition,  threaten  cost and  investment  recovery and impact
               rate structure;

          -    KeySpan's ability to successfully reduce its cost structures;

          -    the  exercise  by LIPA of its right to  acquire  our Long  Island
               generation operations and the deployment of the proceeds received
               in connection therewith;

          -    implementation of new accounting standards;

          -    the successful integration of KeySpan's  subsidiaries,  including
               Eastern, EnergyNorth and their subsidiaries;

          -    the  degree  to  which  KeySpan  develops   unregulated  business
               ventures,  as well  as  federal  and  state  regulatory  policies
               affecting  KeySpan's ability to retain and operate those business
               ventures;

          -    KeySpan's   ability   to   identify   and   make    complementary
               acquisitions,  as well as the  successful  integration  of  those
               acquisitions; and

          -    inflationary trends and interest rates.

         When considering these forward-looking statements, you should keep in
mind the cautionary statements in this document, any prospectus supplement or
term sheet and the documents incorporated by reference. KeySpan will not update
these statements unless the securities laws require it to do so.

                               Keyspan Corporation


         KeySpan Corporation, a New York corporation, was formed in May 1998, as
a result of the business combination of KeySpan Energy Corporation, the parent
of The Brooklyn Union Gas Company, and certain businesses of the Long Island
Lighting Company. KeySpan has assets of more than $11.5 billion and
approximately 2.5 million gas customers throughout the Northeast.

         KeySpan's core business is gas distribution, conducted by its six
regulated gas utility subsidiaries: The Brooklyn Union Gas Company d/b/a KeySpan
Energy Delivery New York and KeySpan Gas East Corporation d/b/a KeySpan Energy
Delivery Long Island distribute gas to customers in the Boroughs of Brooklyn,
Queens and Staten Island in New York City and the Counties of Nassau and Suffolk
on Long Island, respectively; Boston Gas Company, Colonial Gas Company and Essex
Gas Company, each doing business as KeySpan Energy Delivery New England,
distribute gas to customers in eastern and central Massachusetts; and
EnergyNorth Natural Gas, Inc. d/b/a KeySpan Energy Delivery New England
distributes gas to customers in central New Hampshire.

         KeySpan is also a major, and growing, generator of electricity. KeySpan
owns and operates five large generating plants and 42 smaller facilities in
Nassau and Suffolk Counties on Long Island and leases and operates a major
facility in Queens County in New York City. Under contractual arrangements,
KeySpan provides power, electric transmission and distribution services
operation and maintenance, billing and other customer services for approximately
one million electric customers of the Long Island Power Authority on Long
Island.

         KeySpan's other subsidiaries are involved in oil and gas exploration
and production; gas storage; wholesale and retail gas and electric marketing;
appliance service; heating, ventilation and air conditioning installation and
services; large energy-system ownership, installation and management;
telecommunications; energy-related internet activities; fuel cells; water
barging activities, including the hauling of fuel and other cargo; and providing
meter reading equipment and services to municipal utilities. KeySpan also
invests in, and participates in the development of, pipelines and other
energy-related projects, domestically and internationally.

         KeySpan is a registered holding company under the Public Utility
Holding Company Act of 1935, as amended. Therefore, KeySpan's corporate and
financial activities and those of its subsidiaries, including their ability to
pay dividends to KeySpan, are subject to regulation by the Securities and
Exchange Commission. Under KeySpan's holding company structure, KeySpan has no
independent operations or source of income of its own and conducts substantially
all of its operations through its subsidiaries and, as a result, KeySpan depends
on the earnings and cash flow of, and dividends or distributions from, its
subsidiaries to provide the funds necessary to meet its debt and contractual
obligations. Furthermore, a substantial portion of KeySpan's consolidated
assets, earnings and cash flow is derived from the operations of its regulated
utility subsidiaries, whose legal authority to pay dividends or make other
distributions to KeySpan is subject to regulation by state regulatory
authorities.

         KeySpan's principal place of business is One Metro Tech Center,
Brooklyn, New York 11201, and its telephone number is (718) 403-1000.

                                   The Trusts


         KeySpan Trust I, KeySpan Trust II and KeySpan Trust III are Delaware
business trusts. Their principal place of business is c/o KeySpan Corporation,
One Metro Tech Center, Brooklyn, New York 11201, and its telephone number is
(718) 403-1000.

         All of the common securities of the trusts will be owned by KeySpan.
KeySpan will issue a series of subordinated debt securities to the trust in
exchange for the trust common securities and the trust preferred securities.
KeySpan will simultaneously sell the trust preferred securities to the public.
The subordinated debt securities will have the same financial terms as the trust
preferred securities.

         There are five trustees of each trust. Three of them, referred to as
regular trustees, are officers of KeySpan. JPMorgan Chase Bank will act as the
property trustee of each trust, and Chase Manhattan Bank USA, National
Association will act as the Delaware trustee.

                                 Use of Proceeds


         Unless otherwise specified in the applicable prospectus supplement, the
net proceeds from the sale of the offered securities will be used for KeySpan's
general corporate purposes.

 Ratio of Earnings to Fixed Charges and of Earnings to Combined Fixed Charges
                        and Preferred Stock Dividends


         The following table shows KeySpan's consolidated ratio of earnings to
fixed charges and earnings to combined fixed charges and preferred stock
dividends for the periods indicated.


                             Twelve Months                                    Nine Months                                Nine Months
                               Ended                                            Ended                                       Ended
                              December 31,    Twelve Months Ended March 31,    December 31,   Year Ended December 31,  September 30,
                                1996(a)       1997(a)        1998(a)             1998          1999          2000           2001
                                ----          ----           ----                ----          ----          ----           ----
                                                                                                      
Ratio of Earnings to Fixed
   Charges                        2.15           2.21            2.44            (b)           3.23          3.02           2.06
Ratio of Earnings to
   Combined Fixed Charges
   and Preferred stock
   Dividends                      1.81           1.85            2.03            (b)           2.47          2.70           2.01


- ---------------

(a)  Represents  ratio of  earnings to fixed  charges  and  earnings to combined
     fixed changes and preferred stock  dividends,  respectively,  for KeySpan's
     predecessor, Long Island Lighting Company.

(b)  For the nine months ended December 31, 1998,  earnings were insufficient to
     cover fixed charges by $365.0  million and  insufficient  to cover combined
     fixed charges and  preferred  stock  dividends by $409 million.  During the
     nine months ended December 31, 1998, KeySpan incurred the following special
     charges (after tax):  charges associated with the transaction with the Long
     Island  Power  Authority of $107.9  million;  charges  associated  with the
     combination  of Long Island  Lighting  Company's gas and electric  services
     businesses  with KeySpan of $83.5  million;  an impairment  charge of $54.1
     million to  write-down  the value of proved gas  reserves;  and a charge of
     $13.0 million to establish a not-for-profit philanthropic foundation.









                         Description of Debt Securities


         The debt securities offered by this prospectus will be unsecured
obligations of KeySpan and will be either senior or subordinated debt. The
senior debt will be issued under a senior debt indenture and the subordinated
debt will be issued under a subordinated debt indenture The senior debt
indenture and the form of subordinated debt indenture are filed with the SEC as
exhibits to the registration statement of which this prospectus forms a part.
"Debt securities" in this prospectus refers to both the senior debt securities
and the subordinated debt securities.

         The following briefly summarizes the material provisions of the
indentures and the debt securities, other than pricing and related terms
disclosed in the accompanying prospectus supplement or term sheet. The
prospectus supplement will also state whether any of the terms summarized below
do not apply to the series of debt securities being offered. You should read the
more detailed provisions of the indentures, including the defined terms, for
provisions that may be important to you. You should also read the particular
terms of a series of debt securities, which will be described in more detail in
the applicable prospectus supplement. Copies of the indentures may be obtained
from KeySpan or the applicable trustee. So that you may easily locate the more
detailed provisions, the numbers in parentheses below refer to sections in both
indentures (or in only one indenture, if so indicated). Wherever particular
sections or defined terms of the indentures are referred to, those sections or
defined terms are incorporated into this prospectus by reference, and the
statement in this prospectus is qualified by that reference.

         Unless otherwise provided in the applicable prospectus supplement, the
trustee under each indenture will be JPMorgan Chase Bank.

         Capitalized terms used below are defined under "Material covenants -
Defined terms."

Specific terms of each series

         Each time that KeySpan issues a new series of debt securities, the
prospectus supplement or term sheet relating to that new series will specify the
particular amount, price, whether the debt securities are senior or subordinated
debt and other terms of those debt securities. These terms may include:

          -    the title of the debt securities;

          -    any limit on the total principal amount of the debt securities;

          -    the date or dates on which the  principal of the debt  securities
               will be payable or their manner of determination;

          -    the interest  rate or rates of the debt  securities;  the date or
               dates from which interest will accrue on the debt securities; and
               the interest  payment dates and the regular  record dates for the
               debt securities; or, in each case, their manner of determination;

          -    the  place or places  where  the  principal  of and  premium  and
               interest on the debt securities will be paid;

          -    the period or periods within which,  the price or prices at which
               and  the  terms  on  which  any of  the  debt  securities  may be
               redeemed,  in  whole  or in part  at  KeySpan's  option,  and any
               remarketing arrangements;

          -    the terms on which KeySpan would be required to redeem,  repay or
               purchase debt securities required by any sinking fund,  mandatory
               redemption or similar provision; and the period or periods within
               which,  the price or prices at which and the terms and conditions
               on which  the debt  securities  will be so  redeemed,  repaid  or
               purchased in whole or in part;

          -    the denomination in which the debt securities will be issued,  if
               other  than  denominations  of  $1,000  and  any  whole  multiple
               thereof;

          -    the portion of the principal  amount of the debt  securities that
               is payable on the declaration of acceleration of the maturity, if
               other than their principal  amount;  these debt securities  could
               include  original  issue  discount,  or OID,  debt  securities or
               indexed debt securities, which are each described below;

          -    whether and under what circumstances  KeySpan will pay additional
               amounts under any debt  securities  held by a person who is not a
               U.S. person for tax payments,  assessments or other  governmental
               charges  and  whether  KeySpan  has the option to redeem the debt
               securities  which are affected by the additional  amounts instead
               of paying the additional amounts;

          -    the form in which KeySpan will issue the debt securities, whether
               registered,  bearer or both, and any restrictions on the exchange
               of one form of debt securities for another and on the offer, sale
               and delivery of the debt securities in either form;

          -    whether   the  debt   securities   will  be  issuable  as  global
               securities;

          -    whether the amounts of payments of principal of, premium, if any,
               and interest, if any, on the debt securities are to be determined
               with reference to an index,  formula or other method,  and if so,
               the manner in which such amounts will be determined;

          -    if the debt  securities are issuable in definitive  form upon the
               satisfaction  of certain  conditions,  the form and terms of such
               conditions;

          -    any  trustees,   paying  agents,  transfer  agents,   registrars,
               depositories   or  similar   agents  with  respect  to  the  debt
               securities;

          -    any  additions or  deletions to the terms of the debt  securities
               with respect to the events of default or covenants  governing the
               debt securities;

          -    the foreign  currency or units of two or more foreign  currencies
               in which  payment of the principal of and premium and interest on
               any debt securities will be made, if other than U.S. dollars, and
               the  holders'  right,  if any,  to  elect  payment  in a  foreign
               currency  or foreign  currency  unit other than that in which the
               debt securities are payable;

          -    whether  and to what  extent the debt  securities  are subject to
               defeasance  on  terms   different  from  those   described  under
               "Defeasance of the indenture;" and

          -    any other terms of the debt securities that are not  inconsistent
               with the applicable indenture.

         KeySpan may issue debt securities as OID debt securities. OID debt
securities bear no interest or bear interest at below-market rates and are sold
at a discount below their stated principal amount. If KeySpan issues OID debt
securities, the prospectus supplement or term sheet will contain the issue
price, the rate at which interest will accrete, and the date from which such
interest will accrete on the OID debt securities.

         KeySpan may also issue indexed debt securities. Payments of principal
of, and premium and interest on, indexed debt securities are determined with
reference to the rate of exchange between the currency or currency unit in which
the debt security is denominated and any other currency or currency unit
specified by KeySpan, to the relationship between two or more currencies or
currency units or by other similar methods or formulas specified in the
prospectus supplement or term sheet.

         The terms on which a series of debt securities may be convertible into
or exchangeable for other securities of KeySpan or another party will be set
forth in the prospectus supplement relating to that series. The terms will
include provisions as to whether conversion or exchange is mandatory, at the
option of the holder or at KeySpan's option. The terms may include provisions
under which the number of other securities to be received by the holders of a
series of debt securities may be adjusted. (section 301)

Senior debt

         The senior debt securities will rank on an equal basis with all of
KeySpan's other unsecured debt.

Subordinated debt

         Unless the prospectus supplement provides otherwise, the following
provisions will apply to the subordinated debt securities.

         Direct holders of subordinated debt securities should recognize that
contractual provisions in the subordinated debt indenture may prohibit us from
making payments on those securities. Subordinated debt securities are
subordinate and junior in right of payment, to the extent and in the manner
stated in the subordinated debt indenture, to all of our senior indebtedness, as
defined in the subordinated debt indenture, including all debt securities we
have issued and will issue under the senior debt indenture or other indenture
identified in the subordinated debt indenture. (subordinated debt indenture,
section 1401)

         Under the subordinated debt indenture, "senior indebtedness" includes
all of our obligations to pay principal, premium, interest, penalties, fees and
other charges:

          -    for borrowed money;

          -    in the  form of or  evidenced  by  other  instruments,  including
               obligations incurred in connection with our purchase of property,
               assets or businesses;

          -    under capital leases;

          -    under  letters  of  credit,   bankers'   acceptances  or  similar
               facilities;

          -    issued or  assumed in the form of a  deferred  purchase  price of
               property or services, such as master leases;

          -    under swaps and other hedging arrangements;

          -    pursuant to our guarantee of another entity's obligations and all
               dividend obligations guaranteed by us; and

          -    to  satisfy  the  expenses  and  fees  of the  subordinated  debt
               indenture trustee under the subordinated debt indenture.

          The  following   types  of  our   indebtedness   will  not  be  senior
               indebtedness:

          -    indebtedness we owe to a subsidiary of ours;

          -    indebtedness which, by its terms, expressly provides that it does
               not rank senior to the subordinated debt securities;

          -    indebtedness  incurred in the form of trade  accounts  payable or
               accrued liabilities arising in the ordinary course of business;

          -    indebtedness  we owe to any trust (other than the trusts that are
               issuers   of  the   preferred   securities   described   in  this
               prospectus),  or a trustee of such  trust,  partnership  or other
               entity  affiliated  with us, that is our financing  vehicle,  and
               which has issued equity  securities or other  securities that are
               similar to the preferred securities; and

          -    indebtedness we may incur in violation of the  subordinated  debt
               indenture.

         The subordinated debt indenture provides that, unless all principal of
and any premium or interest on the senior indebtedness has been paid in full, no
payment or other distribution may be made in respect of any subordinated debt
securities in the following circumstances:

          -    in the event of any insolvency or bankruptcy proceedings,  or any
               receivership,   liquidation,   reorganization,   assignment   for
               creditors or other similar  proceedings or events involving us or
               our assets; or (subordinated debt indenture, section 1402)

          -    (a) in the event and during the  continuation  of any  default in
               the  payment of  principal,  premium,  if any, or interest on any
               senior  indebtedness beyond any applicable grace period or (b) in
               the event  that any event of default  with  respect to any senior
               indebtedness  has  occurred  and is  continuing,  permitting  the
               direct  holders of that  senior  indebtedness  (or a trustee)  to
               accelerate the maturity of that senior  indebtedness;  whether or
               not the maturity is in fact accelerated  (unless,  in the case of
               (a) or (b),  the  payment  default or event of  default  has been
               cured or waived or ceases to exist and any  related  acceleration
               has  been  rescinded)  or (c)  in the  event  that  any  judicial
               proceeding is pending with respect to a payment  default or event
               of default described in (a) or (b). (subordinated debt indenture,
               section 1403)

         If the trustee under the subordinated debt indenture or any direct
holders of the subordinated debt securities receive any payment or distribution
that is prohibited under the subordination provisions, then the trustee or the
direct holders will have to repay that money to the direct holders of the senior
indebtedness.
(subordinated debt indenture, section 1403)

         Even if the subordination provisions prevent us from making any payment
when due on the subordinated debt securities of any series, we will be in
default on our obligations under that series if we do not make the payment when
due. This means that the trustee under the subordinated debt indenture and the
direct holders of that series can take action against us, but they will not
receive any money until the claims of the direct holders of senior indebtedness
have been fully satisfied. (subordinated debt indenture, section 501)

         The prospectus supplement may include a description of additional terms
implementing the subordination feature.

Form and denomination

         The prospectus supplement or term sheet will describe the form which
the debt securities will have, including insertions, omissions, substitutions
and other variations permitted by the applicable indenture and any legends
required by any laws, rules or regulations. (section 201)

         KeySpan will issue debt securities in denominations of $1,000 and whole
multiples thereof, unless the prospectus supplement or term sheet states
otherwise. (section 302)

Payment

         KeySpan will pay principal of and premium and interest on its
registered debt securities at the place and time described in the debt
securities. KeySpan will pay installments of interest on any registered debt
security to the person in whose name the registered debt security is registered
at the close of business on the regular record date for these payments. KeySpan
will pay principal and premium on registered debt securities only against
surrender of these debt securities. (section 1001) If KeySpan issues debt
securities in bearer form, the prospectus supplement or term sheet will describe
where and how payment will be made.

Material covenants

         The senior debt indenture includes each of the material covenants
discussed below. The subordinated debt indenture includes the material covenant
discussed below under "Limitation on merger, consolidation and sales of assets."

      Lien on assets

         If KeySpan or any of its Gas Utility Subsidiaries mortgages, pledges or
otherwise subjects to any lien the whole or any part of any Property which they
now own or acquire in the future, then KeySpan or that Gas Utility Subsidiary
will secure the debt securities to the same extent and in the same proportion as
the debt or other obligation that is secured by each of those mortgages, pledges
or other liens. The debt securities will remain secured for the same period as
the other debt remains secured. This restriction does not apply, however, to any
of the following:

          -    purchase-money mortgages or liens;

          -    liens on any  property  or asset  that  existed  at the time when
               KeySpan or that Gas Utility Subsidiary  acquired that property or
               asset;

          -    any deposit or pledge to secure  public or statutory  obligations
               or contractual obligations to Long Island Power Authority;

          -    any deposit or pledge with any  governmental  agency  required in
               order to  qualify  KeySpan  or that  Gas  Utility  Subsidiary  to
               conduct its business,  or any part of its business, or to entitle
               it to maintain  self-insurance  or to obtain the  benefits of any
               law relating to workmen's  compensation,  unemployment insurance,
               old age pensions or other social security;

          -    any  deposit  or pledge  with any  court,  board,  commission  or
               governmental  agency as security related to the proper conduct of
               any proceeding before it;

          -    any  mortgage,  pledge  or lien on any  property  or asset of any
               affiliate of KeySpan other than Gas Utility Subsidiaries, even if
               the  affiliate  may have  acquired  that  property  or asset from
               KeySpan or a Gas Utility Subsidiary;

          -    any lien granted over receivables or other monetary or regulatory
               assets granted in connection  with a  securitization  arrangement
               for  those  assets to secure  KeySpan  or one of its Gas  Utility
               Subsidiaries'  monetary  or  regulatory  obligations  incurred in
               relation  to  such  securitization  arrangements,  so long as the
               principal  amount  of  those  obligations  does  not  exceed  the
               aggregate face amount of such receivables or monetary assets;

          -    liens for taxes,  assessments or  governmental  charges or levies
               not yet  delinquent or being  contested in good faith by KeySpan,
               if appropriate reserves have been made;

          -    liens  of  landlords  and  liens  of  mechanics  and  materialmen
               incurred in the ordinary  course of business for sums not yet due
               or being  contested  in good  faith by  KeySpan,  if  appropriate
               reserves have been made;

          -    leases or subleases  granted to others in the ordinary  course of
               business;

          -    easements,   rights-of-way,   restrictions   and  other   similar
               encumbrances  incurred in the  ordinary  course of  business  and
               which do not interfere with the ordinary conduct of business;

          -    liens  incurred in  connection  with the issuance by a state or a
               political  subdivision  of a state of any securities the interest
               on which is exempt from federal income taxes under Section 103 of
               the  Internal  Revenue Code or any other laws or  regulations  in
               effect at the time of the issuance; or

          -    liens for the sole  purpose of  extending,  renewing or replacing
               all or a part of the indebtedness secured by any lien referred to
               in the foregoing clauses or in this clause.

         Notwithstanding the foregoing, KeySpan and its Gas Utility Subsidiaries
may create, incur or permit to exist any lien to secure Indebtedness in addition
to those permitted by the preceding sentence, and renew, extend or replace such
liens, provided that at the time of such creation, incurrence, renewal,
extension or replacement, after giving effect thereto, the aggregate amount of
all such Indebtedness of KeySpan and the Gas Utility Subsidiaries and the
aggregate Attributable Value of all Sales and Leaseback Transactions of KeySpan
and the Gas Utility Subsidiaries at any one time outstanding together shall not
exceed 10% of Consolidated Tangible Assets. As of December 31, 2001,
Consolidated Tangible Assets were $9.86 billion. (senior debt indenture, section
1007)

      Sale and leaseback transactions

         Neither KeySpan nor any of its Gas Utility Subsidiaries may enter into
any Sale and Leaseback unless either:

          -    KeySpan  and its  Gas  Utility  Subsidiaries  would  be  entitled
               pursuant  to  the   "--Liens   on  assets"   covenant  to  create
               Indebtedness  secured by a lien on the  Principal  Property to be
               leased back in an amount equal to the Attributable  Value of such
               Sale and Leaseback  Transaction without the debt securities being
               equally and ratably secured with, or, at KeySpan's option,  prior
               to, that Indebtedness; or

          -    KeySpan or the relevant Gas Utility  Subsidiary,  within 270 days
               after the sale or transfer of the relevant assets shall have been
               made,  applies,  in the case of a sale or transfer  for cash,  an
               amount equal to the net proceeds from the sale or, in the case of
               a sale or transfer  otherwise  than for cash,  an amount equal to
               the fair market  value of the  Principal  Property so leased,  as
               determined  by any two  directors  of KeySpan or the relevant Gas
               Utility Subsidiary, to:

          -    the retirement of  Indebtedness of KeySpan ranking prior to or on
               a parity with the debt securities, incurred or assumed by KeySpan
               or that Gas Utility  Subsidiary which by its terms matures at, or
               is  extendible  or  renewable  at the option of the obligor to, a
               date  more  than  twelve  months  after  the  date of  incurring,
               assuming or guaranteeing such Indebtedness or

          -    the  investment  in any  Principal  Property used in the ordinary
               course of business. (senior debt indenture, section 1008)

      Limitation on merger, consolidation and sales of assets

         KeySpan may not consolidate with or merge into any other entity or
transfer or lease substantially all of its properties and assets to any person
unless:

          -    the successor is organized under the laws of the United States or
               a state thereof;

          -    the successor  assumes by supplemental  indenture the obligations
               of its predecessor-- that is, all of KeySpan's  obligations under
               the debt securities and the applicable indenture; and

          -    after giving effect to the transaction, there is no default under
               the applicable indenture.

         The surviving transferee or lessee corporation will be KeySpan's
successor, and KeySpan will be relieved of all obligations under the debt
securities and the applicable indenture. (sections 801 and 802)

      Defined terms

         "Attributable Value" means, as to any particular lease under which
KeySpan or any of its Gas Utility Subsidiaries is at any time liable as lessee
and at any date as of which the amount thereof is to be determined, the total
net obligations of the lessee for rental payments during the remaining term of
the lease (including any period for which such lease has been extended or may,
at the option of the lessor, be extended) discounted from the respective due
dates thereof to such date at a rate per annum equivalent to the interest rate
inherent in such lease (as determined in good faith by KeySpan in accordance
with generally accepted financial practice) compounded semi-annually.

         "Capital Stock" of any Person means shares, interests, rights to
purchase, warrants, options, participation or other equivalents of or interests
in, however designed, equity of such Person, including any preferred stock, but
excluding any debt securities convertible into such equity.

         "Consolidated Tangible Assets" means, as of the date of any
determination thereof, the total of all assets which would appear on a
consolidated balance sheet of KeySpan and its subsidiaries, prepared in
accordance with U.S. generally accepted accounting principles, or U.S. GAAP, at
their net book values (after deducting related depreciation, depletion and
amortization which, in accordance with U.S. GAAP, should be set aside in
connection with the business conducted), but excluding goodwill, trade names,
trademarks, patents, unamortized debt discount and all other intangible assets
all as determined in accordance with U.S. GAAP.

         "Gas Utility Subsidiaries" means the following subsidiaries of KeySpan
engaged in the distribution and sale at retail of natural gas: The Brooklyn
Union Gas Company d/b/a KeySpan Energy Delivery New York, KeySpan Gas East
Corporation d/b/a KeySpan Energy Delivery Long Island, Boston Gas Company,
Colonial Gas Company, Essex Gas Company, and EnergyNorth Natural Gas, Inc. d/b/a
KEDNE; and any other subsidiary of KeySpan engaged in such activity, provided
such subsidiary would be, at any particular time, a Significant Subsidiary.

         "Indebtedness" means, with respect to any Person, without duplication:

(1)  any liability of that Person:

          -    for borrowed money or under any reimbursement obligation relating
               to a letter of credit or similar instrument;

          -    evidenced by a bond, note, debenture or similar instrument;

          -    to pay the  deferred  purchase  price of  property  or  services,
               except trade accounts  payable  arising in the ordinary course of
               business; or

          -    for the payment of money  relating to any  obligations  under any
               capital  lease  of real  or  personal  property  which  has  been
               recorded as a capitalized lease obligation.

(2)  any  liability  of others  described in the  preceding  clause (1) that the
     Person has guaranteed or that is otherwise its legal  liability or which is
     secured by a lien on that Person's Property;

(3)  any amendment,  supplement,  modification,  deferral, renewal, extension or
     refunding of any  liability of the types  referred to in clauses (1) or (2)
     above; and

(4)  in the case of any of KeySpan's  subsidiaries,  the aggregate preference in
     respect  of  amounts  payable  on the  issued  and  outstanding  shares  of
     preferred  stock of any such  subsidiary  in the event of any  voluntary or
     involuntary  liquidation,  dissolution  or winding up,  excluding  any such
     preference attributable to such shares of preferred stock that are owned by
     such Person or any of its subsidiaries.

         "Person" means any individual, firm, corporation, partnership,
association, joint venture, tribunal, limited liability company, trust,
government or political subdivision or agency or instrumentality thereof, or any
other entity or organization.

         "Principal Property" means the real estate, fixtures, pipelines, mains,
meters, pipes, valves, compressors and other related personal property primarily
used in connection with the transportation, distribution or retail sale of gas
by the Gas Utility Subsidiaries.

         "Property" means any asset, revenue or any other property, including
capital stock, whether tangible or intangible, real or personal, including,
without limitation, any right to receive income.

         "Sale and Leaseback Transaction" means any transaction or series of
related transactions relating to Principal Property now owned or hereafter
acquired whereby KeySpan or one of its Gas Utility Subsidiaries transfers the
Principal Property to a Person and KeySpan or one of its Gas Utility
Subsidiaries leases it from that Person for a period, including renewals, in
excess of three years.

         "Significant Subsidiary" has the meaning specified, as of the date of
the indenture, in Rule 1-02 of Regulation S-X promulgated under the Securities
Act.

Registration of transfer and exchange

         All debt securities issued upon any registration of transfer or
exchange of debt securities will be valid obligations of KeySpan, evidencing the
same debt and entitled to the same rights under the applicable indenture as the
debt securities surrendered in the registration of transfer or exchange.

      Registration of transfer

     Holders of registered  debt  securities  may present their  securities  for
registration  of  transfer  at the  office  of one or more  security  registrars
designated and maintained by KeySpan. (section 305)

         KeySpan will not be required to register the transfer of or exchange
debt securities under the following conditions:

          -    KeySpan  will not be  required  to  register  the  transfer of or
               exchange  any debt  securities  during a period of 15 days before
               any selection of those debt securities to be redeemed.

          -    KeySpan  will not be  required  to  register  the  transfer of or
               exchange any debt securities selected for redemption, in whole or
               in part,  except the  unredeemed  portion of any debt  securities
               being redeemed in part.

          -    KeySpan  will not be  required  to  register  the  transfer of or
               exchange  debt  securities  of any  holder who has  exercised  an
               option to require the repurchase of those debt  securities  prior
               to their  stated  maturity  date,  except the  portion  not being
               repurchased. (section 305)

      Exchange

         At your option, you may exchange your registered debt securities of any
series, except a global security, as set forth below, for an equal principal
amount of other registered debt securities of the same series having authorized
denominations upon surrender to KeySpan's designated agent.

         KeySpan may at any time exchange debt securities issued as one or more
global securities for an equal principal amount of debt securities of the same
series in definitive registered form. In this case KeySpan will deliver to the
holders new debt securities in definitive registered form in the same aggregate
principal amount as the global securities being exchanged.

         The depositary of the global securities may also decide at any time to
surrender one or more global securities in exchange for debt securities of the
same series in definitive registered form, in which case KeySpan will deliver
the new debt securities in definitive form to the persons specified by the
depositary, in an aggregate principal amount equal to, and in exchange for, each
person's beneficial interest in the global securities. (section 305)

         Notwithstanding the above, KeySpan will not be required to exchange any
debt securities if, as a result of the exchange, KeySpan would suffer adverse
consequences under any United States law or regulation.
(section 305)

Global securities

         If KeySpan decides to issue debt securities in the form of one or more
global securities, then KeySpan will register the global securities in the name
of the depositary for the global securities or the nominee of the depositary and
the global securities will be delivered by the trustee to the depositary for
credit to the accounts of the holders of beneficial interests in the debt
securities.

         The prospectus supplement or term sheet will describe the specific
terms of the depositary arrangement for debt securities of a series that are
issued in global form. None of KeySpan, the trustee, any paying agent or the
security registrar will have any responsibility or liability for any aspect of
the records relating to or payments made on account of beneficial ownership
interests in a global debt security or for maintaining, supervising or reviewing
any records relating to these beneficial ownership interests.

Defeasance of the indenture

         Unless otherwise specified in the prospectus supplement or term sheet,
KeySpan can terminate all of its obligations under the applicable indenture with
respect to the debt securities, other than the obligation to pay interest on and
the principal of the debt securities and certain other obligations, at any time
by:

          -    depositing money or U.S. government  obligations with the trustee
               in an amount  sufficient  to pay the principal of and interest on
               the debt securities to their maturity; and

          -    complying with certain other  conditions,  including  delivery to
               the trustee of an opinion of counsel to the effect  that  holders
               of debt  securities will not recognize  income,  gain or loss for
               federal income tax purposes as a result of KeySpan's defeasance.

         In addition, unless otherwise specified in the prospectus supplement or
term sheet, KeySpan can terminate all of its obligations under the applicable
indenture with respect to the debt securities, including the obligation to pay
interest on and the principal of the debt securities, at any time by:

          -    depositing money or U.S. government  obligations with the trustee
               in an amount  sufficient  to pay the principal of and interest on
               the debt securities to their maturity, and

          -    complying with certain other  conditions,  including  delivery to
               the trustee of an opinion of counsel  stating that there has been
               a ruling  by the  Internal  Revenue  Service,  or a change in the
               federal tax law since the date of the  applicable  indenture,  to
               the effect that  holders of debt  securities  will not  recognize
               income,  gain or loss for federal income tax purposes as a result
               of KeySpan's defeasance. (sections 402-404)

Payments of unclaimed moneys

         Moneys deposited with the trustee or any paying agent for the payment
of principal of or premium and interest on any debenture that remains unclaimed
for two years will be repaid to KeySpan at its request, unless the law requires
otherwise. If this happens and you want to claim these moneys, you must look to
KeySpan and not to the trustee or paying agent. (section 409)

Events of default, notices, and waiver

      Events of default

         An "event of default" regarding any series of debt securities is any
one of the following events:

          -    default  for 30 days in the payment of any  interest  installment
               when due and payable;

          -    default in the payment of  principal  or premium  when due at its
               stated  maturity,  by declaration,  when called for redemption or
               otherwise;

          -    default in the performance of any covenant in the debt securities
               or in the  applicable  indenture  by  KeySpan  for 60 days  after
               notice  to  KeySpan  by  the  trustee  or by  holders  of  25% in
               principal  amount  of the  outstanding  debt  securities  of that
               series;

          -    acceleration  of debt  securities of another  series or any other
               indebtedness  of KeySpan or one of its  Significant  Subsidiaries
               for borrowed money, in an aggregate  principal  amount  exceeding
               $25  million  under the terms of the  instrument  or  instruments
               under  which  the  indebtedness  is  issued  or  secured,  if the
               acceleration  is not annulled within 30 days after written notice
               as provided in the applicable indenture;

          -    a final,  non-appealable  judgment  or order for the  payment  of
               money in excess of $25 million rendered against KeySpan or one of
               its  Significant  Subsidiaries  that is not  paid  or  discharged
               within 60 days following entry of such judgment or order;

          -    certain  events  of  bankruptcy,  insolvency  and  reorganization
               involving KeySpan; and

          -    any other event of default of that series  that is  specified  in
               the prospectus supplement or term sheet. (section 501)

         A default regarding a single series of debt securities will not
necessarily constitute a default regarding any other series.

         If an event of default for any series of debt securities occurs and is
continuing (other than an event of default involving the bankruptcy, insolvency
or reorganization of KeySpan), either the trustee or the holders of 25% in
principal amount of the outstanding debt securities of that series may declare
the principal (or, in the case of (a) OID debt securities, a lesser amount as
provided in those OID debt securities or (b) indexed debt securities, an amount
determined by the terms of those indexed debt securities), of all the debt
securities of that series, together with any accrued interest on the debt
securities, to be immediately due and payable by notice in writing to KeySpan.
If it is the holders of debt securities who give notice of that declaration of
acceleration to KeySpan, then they must also give notice to the trustee.
(section 502)

         If an event of default occurs which involves the bankruptcy, insolvency
or reorganization of KeySpan, as set forth above, then all unpaid principal
amounts (or, if the debt securities are (a) OID debt securities, then the
portion of the principal amount that is specified in those OID debt securities
or (b) indexed debt securities, an amount determined by the terms of those
indexed debt securities) and accrued interest on all debt securities of each
series will immediately become due and payable, without any action by the
trustee or any holder of debt securities. (section 502)

         In order for holders of debt securities to initiate proceedings for a
remedy under the applicable indenture, holders of 25% in principal amount of
those debt securities must:

          -    first give notice to KeySpan as provided above;

          -    request that the relevant  trustee  initiate a proceeding  in its
               own name; and

          -    offer  that  trustee a  reasonable  indemnity  against  costs and
               liabilities.

If the trustee still refuses for 60 days to initiate the proceeding, and no
inconsistent direction has been given to the trustee by holders of a majority of
the debt securities of the same series, the holders may initiate a proceeding as
long as they do not adversely affect the rights of any other holders of that
series. (section 507)

         The holders of a majority in principal amount of the outstanding debt
securities of a series may rescind a declaration of acceleration if all events
of default, besides the failure to pay principal or interest due solely because
of the declaration of acceleration, have been cured or waived. (section 502)

         If KeySpan defaults on the payment of any installment of interest and
fails to cure the default within 30 days, or if KeySpan defaults on the payment
of principal when it becomes due, then the trustee may require KeySpan to pay
all amounts due to the trustee, with interest on the overdue principal or
interest payments, in addition to the expenses of collection. (section 503)

         A judgment for money damages by courts in the United States, including
a money judgment based on an obligation expressed in a foreign currency, will
ordinarily be rendered only in U.S. dollars. New York statutory law provides
that a court shall render a judgment or decree in the foreign currency of the
underlying obligation and that the judgment or decree shall be converted into
U.S. dollars at the exchange rate prevailing on the date of entry of the
judgment or decree. Each indenture requires KeySpan to pay additional amounts
necessary to protect holders if a court requires a conversion to be made on a
date other than a judgment date.

      Notices

         The trustee is required to give notice to holders of a series of debt
securities of a default, which remains uncured or has not been waived and that
is known to the trustee, within 90 days after the default has occurred. If a
default occurs in the performance of any covenant in the debt securities or the
applicable indenture, other than a default in the payment of principal of and
premium or interest on any of the debt securities, the trustee shall not give
notice to the holders of debt securities until 60 days after the occurrence of
the default. The trustee may withhold notice of a default if KeySpan and the
trustee determine that doing so is in the best interests of the holders, but may
not withhold the notice in the case of a default in the payment of principal of
and premium or interest on any of the debt securities or the deposit of any
sinking fund payment. (section 602)

      Waiver

         The holders of a majority in principal amount of the outstanding debt
securities of a series may waive any past default or event of default except a
default in the payment of principal of or premium or interest on the debt
securities of that series or a default relating to a provision that cannot be
amended without the consent of each affected holder. (section 513)

Reports

         KeySpan is required under each indenture to file an officer's
certificate with the trustee every year confirming it is complying with all
conditions and covenants in that indenture. (section 1005)

         KeySpan must also file with the trustee copies of its annual reports
and the information and other documents which KeySpan may be required to file
with the SEC under Section 13 or Section 15(d) of the Securities Exchange Act of
1934, as amended. These documents must be filed with the trustee within 15 days
after they are required to be filed with the SEC. If KeySpan is not required to
file the information, documents or reports under either of these Sections, then
KeySpan must file with the trustee and the SEC, in accordance with the rules and
regulations of the SEC, the supplementary and periodic information, documents
and reports which may be required by Section 13 of the Exchange Act, in respect
of a debt security listed and registered on a national securities exchange, as
may be required by the rules and regulations of the SEC.

         Within 30 days of filing the information, documents or reports referred
to above with the trustee, KeySpan must mail to the holders of the debt
securities any summaries of the information, documents or reports which are
required to be sent to the holders by the rules and regulations of the SEC.
(section 704)

Rights and duties of the trustee

         The holders of a majority in principal amount of outstanding debt
securities of any series may direct the time, method and place of conducting any
proceeding for any remedy available to the trustee or exercising any trust or
other power conferred on the trustee. The trustee may decline to follow that
direction if it would involve the trustee in personal liability or would be
illegal. (section 512) During a default, the trustee is required to exercise the
standard of care and skill that a prudent man would exercise under the
circumstances in the conduct of his own affairs. (section 601) The trustee is
not obligated to exercise any of its rights or powers under the applicable
indenture at the request or direction of any of the holders of debt securities
unless those holders have offered to the trustee reasonable security or
indemnity. (section 603)

     The trustee is entitled,  in the absence of bad faith on its part,  to rely
on an officer's certificate before taking action under the applicable indenture.
(section 603)

Supplemental indentures

      Supplemental indentures not requiring consent of holders

         Without the consent of any holders of debt securities, KeySpan and the
trustee may supplement the applicable indenture, among other things, to:

          -    pledge   property  to  the  trustee  as  security  for  the  debt
               securities;

          -    reflect that another entity has succeeded KeySpan and assumed its
               covenants  and  obligations  under  the debt  securities  and the
               applicable indenture;

          -    cure any ambiguity or inconsistency  in the applicable  indenture
               or in the debt securities or make any other provisions  necessary
               or desirable, as long as the interests of the holders of the debt
               securities are not adversely affected in any material respect;

          -    issue  and  establish  the form and  terms of any  series of debt
               securities as provided in the applicable indenture;

          -    add to KeySpan's  covenants  further covenants for the benefit of
               the holders of debt  securities and, if the covenants are for the
               benefit of less than all series of debt securities, stating which
               series are entitled to benefit;

          -    add any  additional  event of  default  and,  if the new event of
               default  applies  to fewer  than all  series of debt  securities,
               stating to which series it applies;

          -    change the trustee or provide for an additional trustee;

          -    provide additional  provisions for bearer debt securities so long
               as the action does not adversely  affect the interests of holders
               of any debt securities in any material respect; or

          -    modify  the  applicable   indenture  in  order  to  continue  its
               qualification  under the Trust Indenture Act of 1939 or as may be
               necessary or desirable in accordance with amendments to that Act.
               (section 901)

      Supplemental indentures requiring consent of holders

         Each indenture permits KeySpan and the trustee, with the consent of the
holders of at least a majority in principal amount of each series of the debt
securities that would be affected by a modification of the applicable indenture,
to supplement that indenture or modify in any way the terms of that indenture or
the rights of the holders of the debt securities. However, without the consent
of each holder of all of the debt securities affected by that modification,
KeySpan and the trustee may not:

          -    reduce the  principal of or premium on or change the stated final
               maturity of any debt security;

          -    reduce the rate of or change the time for  payment of interest on
               any debt security or, in the case of OID debt securities,  reduce
               the rate of accretion of the OID;

          -    change any of KeySpan's  obligations  to pay  additional  amounts
               under the applicable indenture;

          -    reduce or alter the method of  computation  of any amount payable
               upon  redemption,  repayment or purchase of any debt  security by
               KeySpan,  or the time when the redemption,  repayment or purchase
               may be made;

          -    make the principal or interest on any debt security  payable in a
               currency  other than that  stated in the debt  security or change
               the place of payment;

          -    reduce the amount of principal  due on an OID debt  security upon
               acceleration  of maturity or provable in bankruptcy or reduce the
               amount  payable  under the terms of an indexed debt security upon
               acceleration of maturity or provable in bankruptcy;

          -    impair any right of  repayment  or  purchase at the option of any
               holder of debt securities;

          -    in  the  case  of  subordinated   debt  securities,   modify  the
               subordination  provisions in the subordinated debt indenture in a
               manner   adverse  to  the  holders  of  the   subordinated   debt
               securities;

          -    impair the conversion rights of any holder of debt securities;

          -    modify the right of any holder of debt  securities  to receive or
               sue for payment of the  principal or interest on a debt  security
               that  would be due and  payable at the  maturity  thereof or upon
               redemption; or

          -    reduce the principal amount of the outstanding debt securities of
               any series required to supplement the applicable  indenture or to
               waive any of its provisions. (section 902)

         A supplemental indenture which modifies or eliminates a provision
intended to benefit the holders of one series of debt securities will not affect
the rights under the applicable indenture of holders of other series of debt
securities.

Redemption

         The specific terms of any redemption of a series of debt securities
will be contained in the prospectus supplement or term sheet for that series.
Generally, KeySpan must send notice of redemption to the holders at least 30
days but not more than 60 days prior to the redemption date. The notice will
specify:

          -    the principal amount being redeemed;

          -    the redemption date;

          -    the redemption price;

          -    the place or places of payment;

          -    the CUSIP number of the debt securities being redeemed;

          -    whether the redemption is pursuant to a sinking fund;

          -    that on the  redemption  date,  interest,  or, in the case of OID
               debt securities,  original issue discount,  will cease to accrue;
               and

          -    if bearer debt securities are being  redeemed,  that those bearer
               debt securities must be accompanied by all coupons maturing after
               the redemption  date or the amount of the missing coupons will be
               deducted  from  the  redemption   price,  or  indemnity  must  be
               furnished,  and  whether  those  bearer  debt  securities  may be
               exchanged for  registered  debt  securities  not being  redeemed.
               (section 1104)

         On or before any redemption date, KeySpan will deposit an amount of
money with the trustee or with a paying agent sufficient to pay the redemption
price. (section 1103)

         If less than all the debt securities are being redeemed, the trustee
shall select the debt securities to be redeemed using a method it considers
fair. (section 1103) After the redemption date, holders of debt securities which
were redeemed will have no rights with respect to the debt securities except the
right to receive the redemption price and any unpaid interest to the redemption
date. (section 1106)

Concerning the trustee

         KeySpan has customary banking relationships with the trustee under each
indenture, JPMorgan Chase Bank. Among other services, JPMorgan Chase Bank
provides KeySpan with cash management and credit services, including payroll
account, lockbox, foreign exchange and investment custody account services.
JPMorgan Chase Bank also serves or has served as administrative agent and
trustee with respect to other issuances of debt by KeySpan and its subsidiaries
and is a member of a syndicate of banks which is party to several credit
facilities with KeySpan in a total amount of approximately $1.5 billion. In
addition, Chase Securities Inc., an affiliate of JPMorgan Chase Bank, acts as a
placement agent for KeySpan's commercial paper program.

Governing law

     The laws of the State of New York govern each indenture and will govern the
debt securities. (section 112)









                         Description of Preferred Stock


         The following briefly summarizes the material terms of KeySpan's
preferred stock, other than pricing and related terms disclosed in the
accompanying prospectus supplement or term sheet. You should read the particular
terms of any series of preferred stock offered by KeySpan, which will be
described in more detail in any prospectus supplement or term sheet relating to
that series, together with the more detailed provisions of KeySpan's certificate
of incorporation and the certificate of amendment relating to each particular
series of preferred stock for provisions that may be important to you. The
certificate of amendment relating to the particular series of preferred stock
offered by the applicable prospectus supplement and this prospectus will be
filed as an exhibit to a document incorporated by reference in the registration
statement. The prospectus supplement will also state whether any of the terms
summarized below do not apply to the series of preferred stock being offered.

General

         As of December 31, 2001, KeySpan was authorized to issue 83,000,000
shares of preferred stock, par value $.01 per share, 16,000,000 shares of
preferred stock, par value $25 per share and 1,000,000 shares of preferred
stock, par value $100 per share.

         At December 31, 2001, KeySpan had 89,706 shares of 6% Series A ESOP
Convertible Preferred Stock, par value $100 per share, outstanding; 553,000
shares of 7.07% Preferred Stock Series B, par value $100 per share, outstanding;
and 197,000 shares of 7.17% Preferred Stock Series C, par value $100 per share,
outstanding. Shares of Series A Preferred Stock were issued to trustees acting
on behalf of a KeySpan employee benefit plan; they are convertible into shares
of KeySpan's common stock at the option of the holder, redeemable at KeySpan's
option beginning January 1, 2004, and redeemable at the option of the holder
under specified circumstances. Shares of both the Series B and Series C
Preferred Stock are redeemable at KeySpan's option beginning May 28, 2003, and
mandatorily redeemable on May 28, 2005, in the case of the Series B Preferred
Stock, and on May 28, 2008, in the case of the Series C Preferred Stock.
Additionally, if KeySpan fails to pay dividends on either the Series B and
Series C Preferred Stock for four consecutive quarterly dividend periods,
holders of both series will have the right to appoint two directors to KeySpan's
board or directors, who shall remain on the board as long as all dividends on
the Series B and Series C Preferred Stock remain unpaid. You should read the
more detailed provisions of KeySpan's certificate of incorporation or the
certificate of amendment relating to a series of outstanding preferred stock for
provisions that may be important to you.

         Under KeySpan's certificate of incorporation, its board of directors is
authorized to issue shares of preferred stock in one or more series, and to
establish from time to time a series of preferred stock with the following terms
specified:

          -    the number of shares to be included in the series;

          -    the designation,  powers, preferences and rights of the shares of
               the series; and

          -    the  qualifications,  limitations or restrictions of that series,
               except as otherwise stated in the certificate of incorporation.

         Prior to the issuance of any series of preferred stock, KeySpan's board
of directors will create and designate the series as a series of preferred stock
in a certificate of amendment to the certificate of incorporation. The term
"board of directors" includes any duly authorized committee of the board.

         The rights of holders of the preferred stock offered may be adversely
affected by the rights of holders of any shares of preferred stock that may be
issued in the future. The board of directors may cause shares of preferred stock
to be issued in public or private transactions for any proper corporate purpose.
Examples of proper corporate purposes include issuances to obtain additional
financing in connection with acquisitions or otherwise, and issuances to
officers, directors and employees of KeySpan and its subsidiaries pursuant to
benefit plans or otherwise. Shares of preferred stock issued by KeySpan may have
the effect of rendering more difficult or discouraging an acquisition of KeySpan
that is deemed undesirable by its board of directors.

         The preferred stock will be, when issued, fully paid and nonassessable.
Holders of preferred stock will not have any preemptive or subscription rights
to acquire more stock of KeySpan.

         The transfer agent, registrar, dividend disbursing agent and redemption
agent for shares of each series of preferred stock will be named in the
prospectus supplement relating to that series.

Rank

         Unless otherwise specified in the prospectus supplement relating to the
shares of any series of preferred stock, those shares will rank on an equal
basis with each other series of preferred stock and prior to the common stock as
to dividends and distributions of assets.

Dividends

         Each series of preferred stock may provide that holders of that series
are entitled to receive cash dividends, when, as and if declared by KeySpan's
board of directors out of funds legally available for dividends. The rates and
dates of payment of dividends will be set forth in the prospectus supplement
relating to each series of preferred stock. Dividends will be payable to holders
of record of preferred stock as they appear on KeySpan's books or, if
applicable, the records of the depositary referred to below under "Description
of Depositary Shares," on the record dates fixed by the board of directors.
Dividends on any series of preferred stock may be cumulative or noncumulative.

         KeySpan may not declare, pay or set apart for payment dividends on the
preferred stock unless full cumulative dividends on any other series of
preferred stock that ranks on an equal or senior basis have been paid or
sufficient funds have been or are simultaneously set apart for payment for all
of the other series of preferred stock that pay dividends on a cumulative basis;
or the immediately preceding dividend period of the other series of preferred
stock that pay dividends on a noncumulative basis.

         Partial dividends declared on shares of preferred stock and any other
series of preferred stock ranking on an equal basis as to dividends will be
declared pro rata. A pro rata declaration means that the ratio of dividends
declared per share to accrued dividends per share will be the same for both
series of preferred stock.

         Similarly, KeySpan may not declare, pay or set apart for payment
non-stock dividends or make other payments on the common stock or any other
stock of KeySpan ranking junior to the preferred stock until full dividends on
the preferred stock have been paid or set apart for payment for

          -    all prior dividend  periods if the preferred stock pays dividends
               on a cumulative basis; or

          -    the immediately  preceding dividend period if the preferred stock
               pays dividends on a noncumulative basis.

Conversion and Exchange

         The prospectus supplement for any series of preferred stock will state
the terms, if any, on which shares of that series are convertible into or
exchangeable for shares of KeySpan common stock or common stock of a third
party.

Redemption

         If so specified in the applicable prospectus supplement, a series of
preferred stock may be redeemable at KeySpan's or the holder's option and/or may
be mandatorily redeemed. Any partial redemptions of preferred stock will be made
in a way that the board of directors decides is equitable.

         Unless KeySpan defaults in the payment of the redemption price,
dividends will cease to accrue after the redemption date on shares of preferred
stock called for redemption and all rights of holders of those shares will
terminate except for the right to receive the redemption price.

Liquidation Preference

         Upon any voluntary or involuntary liquidation, dissolution or winding
up of KeySpan, holders of each series of preferred stock will be entitled to
receive distributions upon liquidation in the amount set forth in the prospectus
supplement relating to that series of preferred stock, plus an amount equal to
any accrued and unpaid dividends. Those distributions will be made before any
distribution is made on any securities ranking junior relating to liquidation,
including common stock.

         If the liquidation amounts payable relating to the preferred stock of
any series and any other securities ranking on a parity regarding liquidation
rights are not paid in full, the holders of the preferred stock of that series
and other securities will share in any distribution of KeySpan's available
assets on a ratable basis in proportion to the full liquidation preferences.
Holders of that series of preferred stock will not be entitled to any other
amounts from KeySpan after they have received their full liquidation preference.

Voting Rights

         The holders of shares of preferred stock will have no voting rights,
except:

          -    as otherwise stated in the prospectus supplement;

          -    as otherwise stated in the certificate of amendment  establishing
               that series; or

          -    as required by applicable law.









                        Description of Depositary Shares


         The following briefly summarizes the material provisions of the deposit
agreement and of the depositary shares and depositary receipts, other than
pricing and related terms disclosed in the accompanying prospectus supplement or
term sheet. You should read the particular terms of any depositary shares and
any depositary receipts that are offered by KeySpan and any deposit agreement
relating to a particular series of preferred stock which will be described in
more detail in a prospectus supplement or term sheet. The prospectus supplement
or term sheet will also state whether any of the generalized provisions
summarized below do not apply, or additional provisions apply, to the depositary
shares or depositary receipts being offered. A copy of the form of deposit
agreement, including the form of depositary receipt, is incorporated by
reference as an exhibit in the registration statement of which this prospectus
forms a part. You should read the more detailed provisions of the deposit
agreement and the form of depositary receipt for provisions that may be
important to you. So that you may easily locate the more detailed provisions,
the numbers in parentheses below refer to sections in the form of deposit
agreement.

General

         KeySpan may, at its option, elect to offer fractional shares of
preferred stock, rather than full shares of preferred stock. If KeySpan does so,
it will issue receipts for depositary shares, each of which will represent a
fraction of a share of a particular series of preferred stock.

         The shares of any series of preferred stock represented by depositary
shares will be deposited under a deposit agreement between KeySpan and a bank or
trust company selected by KeySpan having its principal office in the United
States and having a combined capital and surplus of at least $50,000,000, as
preferred stock depositary. Each owner of a depositary share will be entitled to
all the rights and preferences of the underlying preferred stock, including
dividend, voting, redemption, conversion and liquidation rights, in proportion
to the applicable fraction of a share of preferred stock represented by that
depositary share.

         The depositary shares will be evidenced by depositary receipts issued
under the deposit agreement. Depositary receipts will be distributed to those
persons purchasing the fractional shares of preferred stock in accordance with
the terms of the applicable prospectus supplement.

Dividends and other distributions

         The preferred stock depositary will distribute all cash dividends or
other cash distributions received in respect of the deposited preferred stock to
the record holders of depositary shares relating to that preferred stock in
proportion to the number of depositary shares owned by those holders. (section
4.01)

         The preferred stock depositary will distribute any property received by
it other than cash to the record holders of depositary shares entitled thereto.
If the preferred stock depositary determines that it is not feasible to make
distributions, it may, with KeySpan's approval, sell that property and
distribute the net proceeds from that sale to those holders. (section 4.02)

Redemption of preferred stock

         If a series of preferred stock represented by depositary shares is to
be redeemed, the depositary shares will be redeemed from the proceeds received
by the preferred stock depositary resulting from the redemption, in whole or in
part, of that series of preferred stock. The depositary shares will be redeemed
by the preferred stock depositary at a price per depositary share equal to the
applicable fraction of the redemption price per share payable in respect of the
shares of preferred stock so redeemed.

         Whenever KeySpan redeems shares of preferred stock held by the
preferred stock depositary, the preferred stock depositary will redeem as of the
same date the number of depositary shares representing shares of preferred stock
so redeemed. If fewer than all the depositary shares are to be redeemed, the
depositary shares to be redeemed will be selected by the preferred stock
depositary by lot or ratably or by any other equitable method as the preferred
stock depositary may decide. (section 2.03)

Conversion of depositary shares

         The depositary shares, as such, are not convertible into shares of
common stock or any other securities or property of KeySpan. Nevertheless, if so
provided in the applicable prospectus supplement, holders may surrender their
depositary receipts to the depositary with written instructions to the
depositary to instruct KeySpan to convert the preferred stock represented by the
depositary shares evidenced by those depositary receipts into whole shares of
common stock. Upon receipt of instructions and any amounts payable in respect of
the conversion, KeySpan will cause the delivery of:

          -    a  certificate  or  certificates  evidencing  the number of whole
               shares of common stock into which the preferred stock represented
               by the depositary shares evidenced by those depositary receipt or
               depositary receipts has or have been converted; and

          -    any money or other property to which the holder is entitled.

         If the depositary shares represented by a depositary receipt are to be
converted in part only, a new depositary receipt or depositary receipts will be
issued for any depositary shares not to be converted. No fractional shares of
common stock will be issued upon conversion, and if any conversion would
otherwise result in a fractional share being issued, an amount will be paid in
cash by KeySpan equal to the value of the fractional interest based on the
closing price of the common stock on the last business day prior to the
conversion. (section 2.04)

Voting deposited preferred stock

         Upon receipt of notice of any meeting at which the holders of any
series of deposited preferred stock are entitled to vote, the preferred stock
depositary will mail the information contained in that notice of meeting to the
record holders of the depositary shares relating to that series of preferred
stock. Each record holder of depositary shares on the record date will be
entitled to instruct the preferred stock depositary to vote the amount of the
preferred stock represented by that holder's depositary shares. The preferred
stock depositary will try to vote the amount of that series of preferred stock
represented by the depositary shares in accordance with those instructions.

         KeySpan will agree to take all actions that the preferred stock
depositary determines as necessary to enable the preferred stock depositary to
vote as instructed. The preferred stock depositary will abstain from voting
shares of any series of preferred stock held by it for which it does not receive
specific instructions from the holders of depositary shares representing those
shares. (section 4.05)

Amendment and termination of the deposit agreement

         The form of depositary receipt evidencing the depositary shares and any
provision of the deposit agreement may at any time be amended by agreement
between KeySpan and the preferred stock depositary. However, any amendment that
materially and adversely alters any existing right of the holders of depositary
shares will not be effective unless the amendment has been approved by the
holders of at least a majority of the depositary shares then outstanding. Every
holder of an outstanding depositary receipt at the time any amendment becomes
effective will be deemed, by continuing to hold the depositary receipt, to
consent and agree to the amendment and to be bound by the deposit agreement,
which has been amended thereby. (section 6.01) The deposit agreement may be
terminated only if:

          -    all outstanding depositary shares have been redeemed; or

          -    final  distribution  in respect of the  preferred  stock has been
               made to the holders of depositary  shares in connection  with any
               liquidation, dissolution or winding up of KeySpan. (section 6.02)

Charges of preferred stock depositary; taxes and other governmental charges

         KeySpan will pay all transfer and other taxes and governmental charges
arising solely from the existence of the depositary arrangements. KeySpan will
also pay charges of the depositary in connection with the initial deposit of
preferred stock and any redemption of preferred stock. Holders of depositary
receipts will pay other transfer and other taxes and governmental charges and
other charges, including a fee for the withdrawal of shares of preferred stock
upon surrender of depositary receipts, as are expressly provided in the deposit
agreement to be for their accounts. (section 5.07)

Resignation and removal of depositary

         The preferred stock depositary may resign at any time by delivering to
KeySpan notice of its intent to do so, and KeySpan may at any time remove the
preferred stock depositary, any resignation or removal to take effect upon the
appointment of a successor preferred stock depositary and its acceptance of the
appointment. The successor preferred stock depositary must be appointed within
60 days after delivery of the notice of resignation or removal and must be a
bank or trust company having its principal office in the United States and
having a combined capital and surplus of at least $50,000,000. (section 5.04)

Miscellaneous

         The preferred stock depositary will forward all reports and
communications from KeySpan which are delivered to the preferred stock
depositary and which KeySpan is required to furnish to the holders of the
deposited preferred stock. (section 5.05)

         Neither the preferred stock depositary nor KeySpan will be liable if it
is prevented or delayed by law or any circumstances beyond its control in
performing its obligations under the deposit agreement. KeySpan's obligations
and those of the preferred stock depositary under the deposit agreement will be
limited to performance in good faith of their duties thereunder and neither
KeySpan nor the preferred stock depositary will be obligated to prosecute or
defend any legal proceeding in respect of any depositary shares, depositary
receipts or shares of preferred stock unless satisfactory indemnity is
furnished. KeySpan and the preferred stock depositary may rely upon written
advice of counsel or accountants, or upon information provided by holders of
depositary receipts or other persons believed to be competent and on documents
believed to be genuine. (section 5.03)









                  Description of the Trust Preferred Securities


         The trust preferred securities will be issued pursuant to amended and
restated declarations of trust. Each declaration will be qualified under the
Trust Indenture Act of 1939. JPMorgan Chase Bank will act as trustee under the
declaration for purposes of the Trust Indenture Act. The terms of the trust
preferred securities will include those stated in the relevant amended and
restated declaration and those made part of the declaration by the Trust
Indenture Act. The declaration will be filed as an exhibit to a document
incorporated by reference in the registration statement of which this prospectus
forms a part.

         The following briefly summarizes the material provisions of the amended
and restated declarations of trust and the trust preferred securities, other
than the pricing and related terms disclosed in an applicable prospectus
supplement. You should also read the particular terms of a series of trust
preferred securities, which will be described in more detail in the applicable
prospectus supplement. The prospectus supplement will also state whether any of
the generalized provisions summarized below do not apply, or additional
provisions apply, to the trust preferred securities being offered. Wherever
particular sections or defined terms of the amended and restated declaration of
trust are referred to, those sections or defined terms are incorporated into
this prospectus by reference, and the statement in this prospectus is qualified
by their reference.

General

         The declaration authorizes the regular trustees to issue both common
and trust preferred securities representing undivided beneficial interests in
the assets of the trust. (section 3.6) KeySpan will own all of the common
securities directly or indirectly. (section 5.2) The common securities will rank
equally, and payments will be made on the common securities on a ratable basis,
with the trust preferred securities. If an event of default under the
declaration occurs and continues, however, the rights of the holders of the
common securities to receive payment of periodic distributions and payments upon
liquidation, redemption and otherwise will be subordinated to the rights of the
holders of the trust preferred securities. (section 7.1) The declaration does
not permit the issuance of any other securities or the incurrence of any
indebtedness by the trust. (section 3.7)

         Under the declaration, the property trustee will hold title to the
subordinated debt securities issued to the trust for the benefit of the holders
of the trust securities. (section 3.8) The payment of distributions out of money
held by the trust, and payments upon redemption of the trust securities or
liquidation of the trust out of money held by the trust, are guaranteed by
KeySpan to the extent described under "Description of the guarantee." The
guarantee will be held by JPMorgan Chase Bank, the guarantee trustee, for the
benefit of the holders of the trust preferred securities. The guarantee does not
cover payment of distributions when the trust does not have sufficient available
funds to pay distributions. In that event, the remedy of a holder of trust
preferred securities is to:

          -    vote to direct  the  property  trustee to  enforce  the  property
               trustee's rights under the subordinated debt securities  (section
               7.5); or

          -    if the failure of the trust to pay  distributions is attributable
               to  KeySpan's  failure  to  pay  interest  or  principal  on  the
               subordinated  debt  securities,  sue KeySpan for  enforcement  of
               payment  to the  holder  of an  amount  equal  to  the  aggregate
               liquidation  amount of its trust preferred  securities.  (section
               3.8)

         The terms, if any, on which the subordinated debt securities and,
therefore, the trust preferred securities may be convertible into common stock
of KeySpan will be set forth in the prospectus supplement relating to those
trust preferred securities. These terms will include provisions as to whether
conversion is mandatory, at the option of the holder or at KeySpan's or the
trust's option. These terms may include provisions under which the number of
shares of common stock to be received by the holders upon conversion may be
adjusted.

Distributions

         Distributions on the trust preferred securities will accrue at the rate
specified in the applicable prospectus supplement. The amount of distributions
payable for any period will be computed on the basis of a 360-day year of twelve
30-day months.

         Distributions on the trust preferred securities will be cumulative,
will accrue from the date the trust issues the trust preferred securities and
will be paid in arrears on the dates specified in the applicable prospectus
supplement, unless they are deferred as described below. (section 7.2)

Deferral of distributions

         KeySpan has the right under the subordinated debt indenture to defer
interest payments on the subordinated debt securities for a period not exceeding
five years during which no interest will be due and payable. A deferral of
interest payments cannot extend, however, beyond the maturity of the
subordinated debt securities. As a consequence of any deferral, distributions on
the trust preferred securities also would be deferred. During a deferral period,
the amount of distributions due to you would continue to accumulate and deferred
distributions will themselves accrue additional distributions. When this
prospectus refers to any payment of distributions, distributions include any of
those additional distributions unless otherwise stated.
(section 7.2)

         Upon the termination of any deferral period and the payment of all
amounts then due, KeySpan may commence a new deferral period as discussed above.
Consequently, there could be several deferral periods of varying lengths
throughout the term of the subordinated debt securities. The regular trustees
will give the holders of the trust preferred securities notice of any deferral
period upon their receipt of notice from KeySpan. (section 3.6) If distributions
are deferred, the deferred distributions on those distributions will be paid to
holders of record of the trust preferred securities as they appear on the
securities register of the trust on the record date following the termination of
the deferral period. (section 7.2) See "--Description of the subordinated debt
securities."

Payment of distributions

         Distributions on the trust preferred securities will be payable to the
holders named on the securities register of the trust at the close of business
on the relevant record dates. As long as the trust preferred securities remain
in book-entry only form, the record dates will be one business day before the
distribution dates. Distributions will be paid through the property trustee who
will hold amounts received on the subordinated debt securities in a property
account for the benefit of the holders of the trust securities. Unless any
applicable laws and regulations and the provisions of the declaration state
otherwise, each payment will be made in accordance with book-entry procedures to
be described in the applicable prospectus supplement.

         If the trust preferred securities do not continue to remain in
book-entry only form, the relevant record dates will conform to the rules of any
securities exchange on which the trust preferred securities are listed. If any
date on which distributions are to be made on the trust preferred securities is
not a business day, then payment of the distributions payable on that date will
be made on the next day which is a business day, and without any interest or
other payment in respect of any delay. However, if that business day is in the
next calendar year, the payment will be made on the immediately preceding
business day. A "business day" means any day other than Saturday, Sunday or any
other day on which banking institutions in New York City are permitted or
required by law to close. (section 7.2)

Redemption

         The trust preferred securities will be redeemed upon the maturity of
the subordinated debt securities or to the extent the subordinated debt
securities are redeemed. The subordinated debt securities will mature on the
date specified in the applicable prospectus supplement, and may be redeemed, in
whole or in part, at any time on or after the date specified in the applicable
prospectus supplement. The subordinated debt securities can also be redeemed at
any time, in whole or in part, in certain circumstances upon the occurrence of a
tax event or an investment company event.

         Upon the maturity of the subordinated debt securities, the proceeds of
their repayment will simultaneously be applied to redeem all outstanding trust
securities at the redemption price. Upon the redemption of the subordinated debt
securities, whether in whole or in part, either at KeySpan's option or pursuant
to a tax or investment company event, the trust will use the cash it receives
upon the redemption to redeem trust securities having an aggregate liquidation
amount equal to the aggregate principal amount of the subordinated debt
securities so redeemed at the redemption price. Holders of trust securities will
be given not less than 30 days' notice, before any redemption. (section 7.3)

Special event redemption

         "Tax event" means that the regular trustees will have received an
opinion of an independent tax counsel experienced in such matters which states
that, as a result of any:

          -    amendment to, or change in, or announced  proposed change in, the
               laws  or  associated  regulations  of the  United  States  or any
               political  subdivision or taxing  authority of the United States;
               or

          -    official   administrative   pronouncement,   action  or  judicial
               decision  interpreting  or  applying  those laws or  regulations,
               there is more than an insubstantial  risk currently or within the
               90 days following that opinion that:

          -    the trust would be required to pay United States  federal  income
               tax  relating to income  accrued or received on the  subordinated
               debt securities;

          -    interest payable to the trust on the subordinated debt securities
               would not be  deductible  by KeySpan  for United  States  federal
               income tax purposes; or

          -    the trust would be required to pay more than a minimal  amount of
               other taxes, duties or other governmental charges. (section 1.1)

         "Investment company event" means that the regular trustees will have
received an opinion of a nationally recognized independent counsel which states
that, as a result of the occurrence of a change in law or regulation or a
written change in interpretation or application of law or regulation by any
legislative body, court, governmental agency or regulatory authority, there is
more than an insubstantial risk that the trust is or will be considered an
"investment company" which is required to be registered under the Investment
Company Act of 1940. (section 1.1)

         This prospectus refers to a tax event and an investment company event
as "special events." If a special event occurs and continues, KeySpan may, upon
not less than 30 days' notice, redeem the subordinated debt securities, in whole
or in part, for cash within 90 days following the occurrence of the special
event.

Redemption procedures

         The trust may not redeem fewer than all of the outstanding trust
preferred securities unless all accrued and unpaid distributions thereon have
been paid.

         Once notice of redemption is given and funds are irrevocably deposited,
distributions will cease to accrue and all rights of holders of trust preferred
securities called for redemption will cease, except the right of the holders to
receive the redemption price, but without interest on the redemption price. If
any redemption date is not a business day, then payment of the redemption price
payable on such date will be made on the succeeding day that is a business day,
without any interest or other payment in respect of any such delay. However, if
that business day falls in the next calendar year, payment will be made on the
preceding business day.

         If payment of the redemption price for any trust preferred securities
is improperly withheld or refused and not paid either by the trust or by KeySpan
under the guarantee, distributions on those trust preferred securities will
continue to accrue at the then applicable rate from the original redemption date
to the date of payment. In this case, the actual payment date will be the
redemption date for purposes of calculating the redemption price.

         In the event that fewer than all of the outstanding trust preferred
securities are to be redeemed, the trust preferred securities will be redeemed
in accordance with the depositary's standard procedures.

         KeySpan or its subsidiaries may, at any time, and from time to time,
purchase outstanding trust preferred securities by tender, in the open market or
by private agreement, provided that it complies with United States federal
securities laws and any other applicable laws. (section 7.4)

Distribution of the subordinated debt securities

         KeySpan will have the right at any time to dissolve the trust. After
satisfying the liabilities of its creditors, the trust may distribute
subordinated debt securities in exchange for the trust preferred securities.
(section 8.2)

         There can be no assurance as to the market prices for either the trust
preferred securities or the subordinated debt securities that may be distributed
in exchange for the trust preferred securities if a dissolution and liquidation
of the trust were to occur. This means that the trust preferred securities that
an investor may purchase, whether pursuant to the offer made by this prospectus
or in the secondary market, or the subordinated debt securities that an investor
may receive if a dissolution and liquidation of the trust were to occur, may
trade at a discount to the price that the investor paid to purchase the trust
preferred securities offered by this prospectus.

Trust enforcement events

         Upon the occurrence of an indenture event of default (as described
below), the property trustee as the sole holder of the subordinated debt
securities will have the right under the indenture to declare the principal of
and interest on the subordinated debt securities to be immediately due and
payable.

     If the property  trustee fails to enforce its rights under the subordinated
debt securities, any holder of trust preferred securities may directly institute
a legal  proceeding  against KeySpan to enforce these rights without first suing
the property trustee or any other person or entity. If a trust enforcement event
has  occurred  and is  continuing  and the event is  attributable  to  KeySpan's
failure to pay interest or principal on the subordinated  debt securities on the
date that  interest or principal is  otherwise  payable,  then a holder of trust
preferred securities may also bring a direct action against KeySpan.

         An "indenture event of default" is an event of default under the
subordinated debt indenture and also constitutes a "trust enforcement event,"
which is an event of default under the declaration relating to the trust
securities. Under the declaration, however, the holder of the common securities
will be deemed to have waived any trust enforcement event relating to the common
securities until all trust enforcement events relating to the trust preferred
securities have been cured, waived or otherwise eliminated. Until any trust
enforcement events relating to the trust preferred securities have been so
cured, waived, or otherwise eliminated, the property trustee will be deemed to
be acting solely on behalf of the holders of the trust preferred securities.
Only the holders of the trust preferred securities will have the right to direct
the property trustee as to matters under the declaration, and therefore the
subordinated debt indenture. (section 2.6)

Voting rights

         Except as described in this prospectus under "Description of the
guarantee--Modification of guarantee; assignment," and except as required by
law, the holders of the trust preferred securities will have no voting rights.

         The holders of a majority in aggregate liquidation amount of the trust
preferred securities have the right to direct any proceeding for any remedy
available to the property trustee, including to:

          -    exercise the remedies available to it under the subordinated debt
               indenture;

          -    waive any past  indenture  event of default and its  consequences
               that is waivable under the subordinated debt indenture; or

          -    consent  to any  amendment,  modification  or  termination  where
               consent is required.

         Any required approval or direction of holders of trust preferred
securities may be given at a separate meeting of holders of trust preferred
securities convened for that purpose, at a meeting of all of the holders of
trust securities or by written consent.

         If an indenture event of default has occurred and not been cured, the
holders of 25% of the aggregate liquidation amount of the trust preferred
securities may direct the property trustee to declare the principal and interest
on the subordinated debt securities due and payable. However, where a consent or
action under the subordinated debt indenture would require the consent of more
than a majority of the aggregate principal amount of debt securities affected
thereby, consent from the holders of that greater percentage would be required.
See "--Description of the subordinated debt securities--Modifications and
amendments."

         Despite the fact that holders of trust preferred securities are
entitled to vote or consent under the circumstances described above, any of the
trust preferred securities that are owned at the time by KeySpan or any entity
directly or indirectly controlling or controlled by, or under direct or indirect
common control with, KeySpan, will not be entitled to vote or consent. Instead,
these trust preferred securities will be treated as if they were not
outstanding.

         The procedures by which holders of trust preferred securities held in
book-entry form may exercise their voting rights will be described in the
applicable prospectus supplement.

         Holders of the trust preferred securities generally will have no rights
to appoint or remove the regular trustees. Instead, the trustees may be
appointed, removed or replaced solely by KeySpan as the indirect or direct
holder of all of the common securities. (section 7.5)

Modification of the declaration

         The declaration may be amended from time to time without the consent of
the holders of the trust preferred securities:

          -    to cure any  ambiguity or correct or  supplement  any  provisions
               that may be defective or inconsistent with any other provision;

          -    to add to the covenants,  restrictions  or obligations of KeySpan
               in its capacity as sponsor of the trust;

          -    to  conform  to any  change  in Rule 3a-5  under  the  Investment
               Company  Act of 1940  or  written  change  in  interpretation  or
               application  of  than  rule  by  any  legislative   body,  court,
               government agency or regulatory authority; or

          -    to modify,  eliminate  or add to any  provisions  as necessary to
               ensure  that the  trust  will be  classified  for  United  States
               federal income tax purposes as a grantor trust at all times or to
               ensure  that the trust will not be  required  to  register  as an
               investment company under the Investment Company Act of 1940.

         Amendments made without the consent of the trust preferred securities
cannot adversely affect in any material respect the rights of the holders of
preferred or common securities.

         The declaration of trust may also be amended as to other matters with
the consent of holders of at least 66 2/3% of the outstanding trust preferred
securities. However, without the consent of each affected holder of preferred or
common securities, the declaration of trust may not be amended to:

          -    change  the  amount or timing of any  distribution  or  otherwise
               adversely  affect the amount of any  distribution  required to be
               made; or

          -    restrict  the  right  of a  holder  to  institute  suit  for  the
               enforcement of any payment.

     Despite the  foregoing,  no  amendment or  modification  may be made to the
declaration if such amendment or modification would

          -    cause the trust to be classified for United States federal income
               tax purposes as other than a grantor trust, or

          -    cause the trust to be deemed  an  "investment  company"  which is
               required to be  registered  under the  Investment  Company Act of
               1940. (section 11.1)

Global securities

         If a trust issues trust preferred securities in the form of one or more
global securities, then that trust will register the global securities in the
name of the depositary for the global securities or the nominee of the
depositary and the global securities will be delivered by the trustee to the
depositary for credit to the accounts of the holders of beneficial interests in
the trust preferred securities.

         The prospectus supplement will describe the specific terms of the
depositary arrangement for trust preferred securities that are issued in global
form. None of KeySpan, the trusts, the relevant trustees, any paying agent or
the security registrar will have any responsibility or liability for any aspect
of the records relating to or payments made on account of beneficial ownership
interests in a global trust preferred security or for maintaining, supervising
or reviewing any records relating to these beneficial ownership interests.
(section 7.12)

Information concerning the property trustee

         Prior to the occurrence of a default relating to the trust securities,
the property trustee undertakes to perform only those duties as are specifically
set forth in the declaration. After a default, the property trustee will
exercise the same degree of care as a prudent individual would exercise in the
conduct of his or her own affairs. The property trustee is under no obligation
to exercise any of the powers vested in it by the declaration at the request of
any holder of trust preferred securities unless offered reasonable indemnity by
the holder against the costs, expenses and liabilities which might be incurred
thereby. (section 6.3)

Paying agent

         If the trust preferred securities do not remain in book-entry only
form, the following provisions will apply:

          -    the property trustee will act as paying agent; and

          -    registration of transfers of trust  preferred  securities will be
               effected  without  charge  (other  than in  respect of any tax or
               other government charge). (section 7.7)

Description of subordinated debt securities

         The subordinated debt securities which KeySpan will issue to the trust
in exchange for its common and preferred securities will be issued pursuant to
the subordinated debt indenture between KeySpan and JPMorgan Chase Bank, as the
indenture trustee, described in "Description of Debt Securities" above. The
subordinated debt indenture will be qualified under the Trust Indenture Act of
1939. The terms of the subordinated debt securities will include those stated in
the subordinated debt indenture and those made a part of that indenture by the
Trust Indenture Act. The following summary of the material terms of the
subordinated debt securities is not intended to be complete and is qualified by
the applicable prospectus supplement, the subordinated debt indenture, the Trust
Indenture Act and other applicable law. The form of subordinated debt indenture
(including all amendments) has been filed with the SEC as an exhibit to, and is
incorporated by reference in, the registration statement of which this
prospectus forms a part.

      General

         The subordinated debt securities will be issued as unsecured debt under
the subordinated debt indenture. The subordinated debt securities will be
limited in aggregate principal amount to the sum of the aggregate stated
liquidation amount of the trust preferred securities and the common securities
and will be subordinated and junior in right of payment to all of KeySpan's
senior debt and may be subordinated to some of KeySpan's subordinated debt.

         The entire principal amount of the subordinated debt securities will
mature and become due and payable, together with any accrued and unpaid interest
thereon, on the date specified in the applicable prospectus supplement.

         If subordinated debt securities are distributed to holders of trust
preferred securities in liquidation of the holders' interests in the trust, the
subordinated debt securities will initially be issued in the form of one or more
global securities under depositary arrangements similar to those in effect for
the trust preferred securities. In the event subordinated debt securities are
issued in certificated form, principal and interest will be payable, the
transfer of the subordinated debt securities will be registrable and
subordinated debt securities will be exchangeable for securities of other
denominations of a like aggregate principal amount at the corporate trust office
of the indenture trustee in New York, New York. (section 7.2)

      Redemption

         KeySpan shall have the right to redeem the subordinated debt securities
as described above under "Description of the Trust Preferred
Securities?Redemption." The redemption price will be specified in the applicable
prospectus supplement.

      Interest

         The subordinated debt securities will bear interest at the rate
specified in the applicable prospectus supplement, payable in arrears on the
dates specified in the applicable prospectus supplement, unless interest is
deferred as described below. Interest will be paid to the person in whose name
the subordinated debt security is registered, with limited exceptions, at the
close of business on the business day next preceding the interest payment date.
In the event the subordinated debt securities shall not continue to remain in
book-entry only form, KeySpan will select appropriate record dates.

         The amount of interest payable for any period will be computed on the
basis of a 360-day year of twelve 30-day months. The amount of interest payable
for any period shorter than a full period will be computed on the basis of the
actual number of days elapsed per 30-day month. If any date on which interest is
payable on the subordinated debt securities is not a business day, then payment
of the interest payable on that date will be made on the succeeding day that is
a business day, and without any interest or other payment in respect of any
delay. However, if that business day is in the succeeding calendar year, then
the payment shall be made on the preceding business day, in each case with the
same force and effect as if made on that date.

      Option to defer interest payments

         KeySpan can defer interest payments for up to five years. However, no
deferral period may extend beyond the maturity of the subordinated debt
securities. At the end of the deferral period, KeySpan will pay all interest
then accrued and unpaid.

         During any deferral period, neither KeySpan nor any of its subsidiaries
will be permitted to:

          -    pay a dividend or make any other payment or  distribution  on its
               capital stock;

          -    redeem,  purchase  or make a  liquidation  payment  on any of its
               capital stock;

          -    make  an  interest,  principal  or  premium  payment,  or  repay,
               repurchase or redeem,  any of its debt securities that rank equal
               with or junior to the subordinated debt securities; or

          -    make any  guarantee  payment  with  respect to any  guarantee  by
               KeySpan of debt  securities  of any of its  subsidiaries,  if the
               guarantee  ranks  equal to or  junior  to the  subordinated  debt
               securities.

         During any deferral period, however, KeySpan will be permitted to:

          -    pay dividends or  distributions  by way of issuance of its common
               stock;

          -    make payments under the guarantee in respect of the preferred and
               common securities;

          -    declare or pay a dividend in  connection  with any  shareholders'
               rights  plan,  or the  issuing  of  stock  under  such a plan  or
               repurchase those rights; and

          -    purchase  common stock relating to the issuing of common stock or
               rights under any of its benefit plans.

         KeySpan has no present intention of exercising its right to defer
payments of interest by extending the interest payment period on the
subordinated debt securities.

         If the property trustee is the sole holder of the subordinated debt
securities, KeySpan will give the regular trustees and the property trustee
notice of its election to defer interest payments one business day prior to the
earlier of:

          -    the date distributions on the trust preferred securities would be
               payable, if not for the deferral period, or

          -    the date the regular  trustees are required to give notice to the
               NYSE  or  other  applicable  self-regulatory  organization  or to
               holders of the trust  preferred  securities of the record date or
               the  date  the  distribution  would  be  payable,  if not for the
               deferral period,

but in any event one business day prior to such record date. The regular
trustees will give notice of KeySpan's selection of the deferral period to the
holders of the trust preferred securities.

         If the property trustee is not the sole holder of the subordinated debt
securities, KeySpan shall give the holders of the subordinated debt securities
notice of its election to defer interest payments ten business days prior to the
earlier of:

          -    the next succeeding interest payment date or

          -    the date upon which  KeySpan is  required  to give  notice to the
               NYSE  or  other  applicable  self-regulatory  organization  or to
               holders  of the  subordinated  debt  securities  of the record or
               payment date of such related interest payment,

but in any event two business days prior to the record date.

      Indenture events of default

         If any indenture event of default shall occur and be continuing, the
property trustee, as the holder of the subordinated debt securities, will have
the right to declare the principal of and the interest on the subordinated debt
securities and any other amounts payable under the subordinated debt indenture
to be immediately due and payable. An indenture event of default also
constitutes a trust enforcement event. The holders of trust preferred securities
in limited circumstances have the right to direct the property trustee to
exercise its rights as the holder of the subordinated debt securities. See
"Description of the trust preferred securities?Trust enforcement events" and
"?Voting rights." (section 7.6)

         Despite the foregoing, if a trust enforcement event has occurred and is
continuing and that event is attributable to KeySpan's failure to pay interest
or principal on the subordinated debt securities when interest or principal is
payable, KeySpan acknowledges that, in that event, a holder of trust preferred
securities may sue for payment. KeySpan may not amend the subordinated debt
indenture to remove this right to bring a direct action without the prior
written consent of all of the holders of trust preferred securities.

      Miscellaneous

         The subordinated debt indenture provides that KeySpan will pay all fees
and expenses related to:

          -    the  issuance  and  exchange  of the  trust  securities  and  the
               subordinated debt securities;

          -    the organization, maintenance and dissolution of the trust;

          -    the retention of the trustees; and

          -    the  enforcement  by the  property  trustee  of the rights of the
               holders of the trust preferred securities.

Description of the guarantee

         The guarantee to be executed and delivered by KeySpan for the benefit
of the holders of trust preferred securities will be qualified as an indenture
under the Trust Indenture Act of 1939. JPMorgan Chase Bank will act as guarantee
trustee for purposes of the Trust Indenture Act. The terms of the guarantee will
include those set forth in the guarantee and those made part of the guarantee by
the Trust Indenture Act. The guarantee will be filed as an exhibit to a document
incorporated by reference in the registration statement of which this prospectus
forms a part.

         The following briefly summarizes the material provisions of the
guarantee. You should also read the particular terms of a guarantee, which will
be described in more detail in the applicable prospectus supplement. The
prospectus supplement will also state whether any of the generalized provisions
summarized below do not apply, or additional provisions apply, to the trust
preferred securities being offered. Wherever particular sections or defined
terms of the guarantee are referred to, those sections or defined terms are
incorporated into this prospectus by reference, and the statement in this
prospectus is qualified by their reference.

      General

         Under, and to the extent set forth in, the guarantee, KeySpan will
irrevocably and unconditionally agree to pay in full to the holders of the trust
preferred securities, as and when due, regardless of any defense, right of
set-off or counterclaim which the trust may have or assert, the following
payments without duplication:

          -    any accrued and unpaid distributions that are required to be paid
               on the trust  preferred  securities,  to the extent the trust has
               funds available for distributions;

          -    the redemption price per trust preferred security,  to the extent
               the trust has funds available for redemptions; and

          -    upon  a  voluntary  or  involuntary  dissolution,  winding-up  or
               liquidation  of the  trust,  other  than in  connection  with the
               distribution  of  subordinated  debt securities to the holders of
               trust preferred securities, the lesser of:

          -    the  aggregate   liquidation   amount  of  the  trust   preferred
               securities and all accrued and unpaid distributions thereon, or

          -    the amount of assets of the trust  remaining for  distribution to
               holders of the trust  preferred  securities upon a liquidation of
               the trust. (section 5.1)

      Status of the guarantee

         The guarantee will constitute an unsecured obligation of KeySpan and
will rank:

          -    subordinate  and junior in right of  payment to all of  KeySpan's
               other liabilities,

          -    on a parity with the most senior  preferred or  preference  stock
               now or hereafter  issued by KeySpan and with any guarantee now or
               hereafter  entered  into  by  KeySpan  in  respect  of any  trust
               preferred securities of any of its affiliates, and

          -    senior to KeySpan common stock. (section 6.2)

         The guarantee will not place a limitation on the amount of additional
senior debt that KeySpan may incur.

         The guarantee will constitute a guarantee of payment and not of
collection -- that is, the guaranteed party may institute a legal proceeding
directly against KeySpan to enforce its rights under the guarantee without first
instituting a legal proceeding against any other person or entity. (section 5.5)
The guarantee will not be discharged except by payment of the guarantee payments
in full to the extent not paid by the trust or upon distribution of the
subordinated debt securities to the holders of the trust preferred securities in
exchange for all their trust preferred securities. (section 7.1)

         The guarantee, when taken together with KeySpan's obligations under the
subordinated debt securities, the subordinated debt indenture and the
declaration, including KeySpan's obligations to pay costs, expenses, debts and
liabilities of the trust, other than those relating to trust securities, will
provide a full and unconditional guarantee on a subordinated basis by KeySpan of
payments due on the trust preferred securities. See "Effect of obligations under
the subordinated debt securities and the guarantee."

      Important covenants

         In the guarantee, KeySpan will covenant that, so long as any trust
securities remain outstanding, if:

          -    there  shall  have  occurred  any  event  of  default  under  the
               subordinated debt indenture,

          -    KeySpan  shall be in default  with  respect to its payment of any
               obligations under the guarantee, or

          -    KeySpan shall have given notice of its election to defer interest
               payments  and shall not have  rescinded  that  notice,  and while
               interest is deferred,

then KeySpan will not, and will not permit any subsidiary to:

          -    declare  or pay any  dividends  or  distributions  on, or redeem,
               purchase,  acquire or make a liquidation payment with respect to,
               any of KeySpan's capital stock, or

          -    make any payment of principal, interest or premium, if any, on or
               repay,  repurchase or redeem any of its debt securities that rank
               on a parity with or junior in interest to the  subordinated  debt
               securities  or make any  guarantee  payments  with respect to any
               guarantee  by  KeySpan  of  the  debt  securities  of  any of its
               subsidiaries if the guarantee ranks on a parity with or junior in
               interest to the subordinated debt securities, other than:

          -    dividends or distributions in common stock of KeySpan,

          -    payments  under the  guarantee  made by KeySpan in respect of the
               trust securities of the trust,

          -    any   declaration   of  a  dividend   in   connection   with  the
               implementation of a shareholders' rights plan, or the issuance of
               stock under any rights plan in the future,  or the  redemption or
               repurchase of any rights under a rights plan, and

          -    purchases of common stock related to the issuance of common stock
               or rights under any of its benefit plans. (section 6.1)

      Events of default

         An event of default under the guarantee will occur upon KeySpan's
failure to perform any of its payment or other obligations required by the
guarantee. The holders of a majority in aggregate liquidation amount of the
trust preferred securities have the right to direct the time, method and place
of conducting any proceeding for any remedy available to the guarantee trustee
in respect of the guarantee or to direct the exercise of any trust or power
conferred upon the guarantee trustee under the guarantee.

         If the guarantee trustee fails to enforce its rights under the
guarantee, any holder of related trust preferred securities may directly sue
KeySpan to enforce the guarantee trustee's rights under the guarantee without
first suing the trust, the guarantee trustee or any other person or entity.
(section 5.4)

         KeySpan, as guarantor, will be required to file annually with the
guarantee trustee a certificate as to whether or not it is in compliance with
all the conditions and covenants applicable to it under the guarantee.
(section 2.4)

      Modification of guarantee; assignment

         The guarantee may be amended only with the prior approval of the
holders of not less than 66 2/3% in aggregate liquidation amount of the
outstanding trust preferred securities and common securities. No vote will be
required, however, for any changes that do not materially adversely affect the
rights of holders of the securities. All guarantees and agreements contained in
the guarantee shall bind KeySpan's successors, assignees, receivers, trustees
and representatives and shall inure to the benefit of the holders of the trust
preferred securities then outstanding. (section 9.2)

      Information concerning the guarantee trustee

         Prior to the occurrence of a default relating to the guarantee, the
guarantee trustee undertakes to perform only the duties as are specifically set
forth in the guarantee. After a default, the guarantee trustee will exercise the
same degree of care as a prudent individual would exercise in the conduct of his
or her own affairs. Provided that the foregoing requirements have been met, the
guarantee trustee is under no obligation to exercise any of the powers vested in
it by the guarantee at the request of any holder of trust preferred securities
unless it is offered reasonable indemnity against the costs, expenses and
liabilities that might be incurred in doing so. (section 3.1)

      Termination of the guarantee

         The guarantee will terminate as to the trust preferred securities upon
full payment of the redemption price of all trust preferred securities, upon
distribution of the subordinated debt securities to the holders of the trust
preferred securities or upon full payment of the amounts payable upon
liquidation of the trust. The guarantee will continue to be effective or will be
reinstated, as the case may be, if at any time any holder of trust preferred
securities must restore payment of any sums paid under the trust preferred
securities or the guarantee. (section 7.1)

      Governing law

     The guarantee will be governed by and construed in accordance with the laws
of New York. (section 9.5)

Effect of obligations under the subordinated debt securities and the guarantee

         The sole purpose of the trust is to issue the trust securities in
exchange for KeySpan's subordinated debt securities. As long as payments of
interest and other payments are made when due on the subordinated debt
securities, those payments will be sufficient to cover the distributions and
payments due on the trust securities. This is due to the following factors:

          -    the aggregate  principal  amount of subordinated  debt securities
               will be  equal  to the sum of the  aggregate  stated  liquidation
               amount of the trust securities;

          -    the interest rate and the interest and other payment dates on the
               subordinated debt securities will match the distribution rate and
               distribution  and other  payment  dates  for the trust  preferred
               securities;

          -    under the subordinated debt indenture,  KeySpan will pay, and the
               trust will not be obligated to pay,  directly or indirectly,  all
               costs,  expenses  and  obligations  of the trust other than those
               relating to the trust securities; and

          -    the declaration  further provides that the trustees may not cause
               or  permit  the  trust  to  engage  in any  activity  that is not
               consistent with the purposes of the trust.

         Payments of distributions, to the extent there are available funds, and
other payments due on the trust preferred securities, to the extent there are
available funds, are guaranteed by KeySpan to the extent described in this
prospectus. If KeySpan does not make interest payments on the subordinated debt
securities, the trust will not have sufficient funds to pay distributions on the
trust preferred securities. The guarantee is a subordinated guarantee in
relation to the trust preferred securities. The guarantee does not apply to any
payment of distributions unless and until the trust has sufficient funds for the
payment of those distributions.
See "Description of the guarantee."

         The guarantee covers the payment of distributions and other payments on
the trust preferred securities only if and to the extent that KeySpan has made a
payment of interest or principal or other payments on the subordinated debt
securities. The guarantee, when taken together with KeySpan's obligations under
the subordinated debt securities and the subordinated debt indenture and its
obligations under the declaration, will provide a full and unconditional
guarantee of distributions and all other amounts due on the trust preferred
securities.

         KeySpan acknowledges that the guarantee trustee shall enforce the
guarantee on behalf of the holders of the trust preferred securities. If KeySpan
fails to make payments under the guarantee, the guarantee allows the holders of
the trust preferred securities to direct the guarantee trustee to enforce its
rights under the guarantee. If the guarantee trustee fails to enforce the
guarantee, any holder of trust preferred securities may directly sue KeySpan to
enforce the guarantee trustee's rights under the guarantee. Holders do not need
to first sue the trust, the guarantee trustee, or any other person or entity. A
holder of trust preferred securities may also directly sue KeySpan to enforce
its right to receive payment under the guarantee. Holders do not first need to:

          -    direct  the  guarantee  trustee  to  enforce  the  terms  of  the
               guarantee; or

          -    sue the trust or any other person or entity. (guarantee,  section
               5.4)









                           Description of Common Stock


General

         KeySpan's certificate of incorporation presently authorizes the
issuance of 450,000,000 shares of common stock, par value $0.01 per share. As of
December 31, 2001, there were 139,429,749 shares of common stock outstanding. As
of such date, KeySpan had approximately 82,300 shareholders of record. The
outstanding shares of common stock are, and the additional shares of common
stock that may be offered hereby upon issuance will be, fully paid and
nonassessable.

         The following briefly summarizes material provisions of KeySpan's
common stock, KeySpan's certificate of incorporation and the related rights
agreement and anti-takeover provisions of New York law.

Dividends

         The holders of KeySpan common stock are entitled to dividends and other
distributions out of assets legally available at such times and in such amounts
as KeySpan's directors may determine from time to time. Although KeySpan
contemplates the payment of dividends, the payment of future dividends is
dependent upon, among other factors, action by its board of directors, its
financial condition, future earnings and the availability of cash.

Dividend limitations

         No dividends may be declared on common stock unless all cumulative
dividends on outstanding preferred stock have been paid or declared and set
apart for payment.

Voting rights

         Each share of common stock is entitled to one vote on all matters to be
voted on by shareholders. Ordinarily, the holders of KeySpan common stock have
sole voting power to elect KeySpan's directors; however, holders of KeySpan
preferred stock could have the power to elect directors. KeySpan's certificate
of incorporation provides that the board of directors may, from time to time,
determine the extent of the voting rights, if any, of the shares of each series
of preferred stock and determine whether the shares of any series having voting
rights shall have multiple votes per share. The common stock does not have
cumulative voting rights.

Preemptive rights

         Holders of KeySpan common stock do not have preemptive rights to
purchase additional shares of common stock or securities convertible into shares
of common stock.

Liquidation rights

         In the event of liquidation, the holders of KeySpan common stock are
entitled to all assets that remain after satisfaction of creditors and the
liquidation preferences of outstanding preferred stock.

         The number, designation, relative rights, preferences and limitations
of the shares of the preferred stock, and of KeySpan common stock, are stated in
full in its certificate of incorporation.

Anti-takeover effects of provisions of New York law and KeySpan's certificate of
incorporation

         Certain provisions of New York law and KeySpan's certificate of
incorporation could make more difficult or delay the acquisition of KeySpan by
means of a tender offer, a proxy contest or otherwise and the removal of
incumbent directors. These provisions are intended to discourage certain types
of coercive takeover practices and inadequate takeover bids, even though such a
transaction may offer KeySpan's shareholders the opportunity to sell their stock
at a price above the prevailing market price. KeySpan's board of directors
believes that these provisions are appropriate to protect the interests of
KeySpan and of its shareholders.

      New York anti-takeover statute

         KeySpan is subject to the business combination provisions of Section
912 of the New York Business Corporation Law and expects to continue to be so
subject if and for so long as it has a class of securities registered under
Section 12 of the Securities Exchange Act of 1934, as amended. Section 912
provides, with specified exceptions, that a New York corporation may not engage
in a business combination, such as a merger, consolidation, recapitalization or
disposition of stock, with any "interested shareholder" for a period of five
years from the date that person first became an interested shareholder unless:

          -    the  transaction  resulting  in a person  becoming an  interested
               shareholder  was  approved  by  the  board  of  directors  of the
               corporation   prior  to  that  person   becoming  an   interested
               shareholder;

          -    the business combination is approved by the holders of a majority
               of the  outstanding  voting  stock not  beneficially  owned by an
               interested shareholder;

          -    the  business   combination  is  approved  by  the  disinterested
               shareholders at a meeting called no earlier than five years after
               the  date  that  the  interested   shareholder  first  became  an
               interested shareholder; or

          -    the business combination meets certain valuation requirements for
               the capital stock of the New York corporation.

         An interested shareholder is defined as any person that is the
beneficial owner of 20% or more of the outstanding voting stock of a New York
corporation or is an affiliate or associate of the corporation that at any time
during the prior five years was the beneficial owner, directly or indirectly, of
20% or more of the then outstanding voting stock. A business combination
includes mergers, asset sales and other transactions resulting in a financial
benefit to the interested shareholder.

         This statute could prohibit or delay the accomplishment of mergers,
tender offers or other takeover or change in control attempts with respect to
KeySpan and, accordingly, may discourage attempts to acquire it.

      "Anti-Greenmail"

         KeySpan is subject to Section 513 of New York's Business Corporation
Law, which provides that no domestic corporation may purchase or agree to
purchase more than 10% of its stock from a shareholder who has held the shares
for less than two years at any price that is higher than the market price unless
the transaction is approved by both the corporation's board of directors and a
majority of the votes of all outstanding shares entitled to vote thereon at a
meeting of shareholders, unless the certificate of incorporation requires a
greater percentage or the corporation offers to purchase shares from all the
holders on the same terms. KeySpan's certificate of incorporation does not
currently provide for a higher percentage.

      No shareholder action by written consent

         KeySpan's certificate of incorporation eliminates the ability of
shareholders to act by written consent. It further provides that special
meetings of KeySpan shareholders may be called only by its board of directors.

          Advance notice  requirements  for  shareholder  proposals and director
     nominations

         KeySpan's by-laws include advance notice and informational requirements
and time limitations on any director nomination or any new proposal that a
shareholder wishes to make at an annual meeting of shareholders. In general, a
shareholder's notice of a director nomination or proposal will be timely if
delivered to the secretary of KeySpan at its principal executive offices not
less than 60 days nor more than 90 days prior to the scheduled date of the
annual meeting. These provisions may preclude shareholders from bringing matters
before an annual meeting or from making nominations for directors at these
meetings.

      Director vacancies and removal

         KeySpan's certificate of incorporation provides that vacancies in its
board of directors may be filled only by the affirmative vote of a majority of
the remaining directors. The certificate of incorporation also provides that
directors may be removed from office only with cause and only by the affirmative
vote of holders of a majority of the shares then entitled to vote at an election
of directors.

Rights agreement

         Under a rights agreement, each share of KeySpan common stock has
associated with it one preferred stock purchase right. Each of these rights
entitles its holder to purchase, at a purchase price of $95, subject to
adjustment, "units" of one one-hundredth of a share of Series D preferred stock
under circumstances provided for in the rights agreement.

         The purpose of the rights agreement is to:

          -    give  KeySpan's  board of directors the  opportunity to negotiate
               with any persons seeking to obtain control of KeySpan;

          -    deter acquisitions of voting control of KeySpan without assurance
               of fair and equal treatment of all KeySpan shareholders; and

          -    prevent a person from acquiring in the market a sufficient amount
               of KeySpan  voting  power to be in a position  to block an action
               sought to be taken by KeySpan's shareholders.

The exercise of the rights would cause substantial dilution to a person
attempting to acquire KeySpan on terms not approved by its board of directors
and therefore would significantly increase the price that person would have to
pay to complete the acquisition. The rights agreement may deter a potential
acquisition or tender offer.

         Until a "distribution date" occurs, the rights will:

          -    not be exercisable;

          -    be represented by the same certificate that represents the shares
               with which the rights are associated; and

          -    trade together with those shares.

The rights will expire at the close of business on March 30, 2009, unless
earlier redeemed or exchanged by KeySpan.

         Following a "distribution date," the rights would become exercisable
and KeySpan would issue separate certificates representing the rights, which
would trade separately from the shares of KeySpan common stock.

         A "distribution date" would occur upon the earlier of:

          -    ten business days after a public announcement that the person has
               become an "acquiring person"; or

          -    ten  business  days after a person  commences  or  announces  its
               intention  to  commence  a tender  or  exchange  offer  that,  if
               successful,  would  result in the person  becoming an  "acquiring
               person."

         Under the rights agreement, a person becomes an "acquiring person" if
the person, alone or together with a group, acquires beneficial ownership of 20%
or more of the outstanding shares of KeySpan common stock. However, an
"acquiring person" shall not include KeySpan, any of its subsidiaries, any of
its employee benefit plans or any person or entity acting pursuant to such
employee benefit plans. The rights agreement also contains provisions designed
to prevent the inadvertent triggering of the rights by institutional or certain
other shareholders.

         If any person becomes an acquiring person, each holder of a right,
other than the acquiring person, will be entitled to purchase, at the purchase
price, a number of shares of KeySpan common stock having a market value two
times the purchase price. If, following a public announcement that a person has
become an acquiring person:

          -    KeySpan  merges or enters into any similar  business  combination
               transaction and KeySpan is not the surviving corporation; or

          -    50% or more of KeySpan's  assets,  cash flow or earning  power is
               sold or transferred,

each holder of a right, other than the acquiring person, will be entitled to
purchase a number of shares of common stock of the surviving entity having a
market value two times the purchase price.

         After a person becomes an acquiring person, but prior to that person
acquiring 50% of KeySpan common stock, KeySpan's board of directors may exchange
the rights, other than rights owned by the acquiring person, at an exchange
ratio of one share of common stock, or one one-hundredth of a share of Class D
Preferred Stock, or of a share of KeySpan's preferred stock having equivalent
rights, preferences and privileges, for each right.

         At any time until the tenth business day following a public
announcement that a person has become an acquiring person, KeySpan's board of
directors may redeem all of the rights at a redemption price of $.01 per right.
On the redemption date, the rights will expire and the only entitlement of the
holders of rights will be to receive the redemption price.

         A holder of rights will not, as such, have any rights as a shareholder
of KeySpan, including rights to vote or receive dividends.

         At any time prior to the distribution date, KeySpan's board of
directors may amend any provisions in the rights agreement. After the
distribution date, the board of directors may amend the provisions of the rights
agreement in order to:

          -    cure any ambiguity;

          -    shorten or lengthen any time period  under the rights  agreement;
               or

          -    make changes that will not adversely  affect the interests of the
               holders of rights;

provided, that no amendment may be made when the rights are not redeemable.

         The distribution of the rights will not be taxable to KeySpan or its
shareholders. A shareholder may recognize taxable income when the rights become
exercisable for common stock of KeySpan or an acquiring company.

Limitations of liability and indemnification matters

         As permitted by the New York Business Corporation Law, KeySpan's
certificate of incorporation provides that a director is not personally liable
to KeySpan or its shareholders for damages for any breach of duty in his
capacity as a director unless a judgment or other final adjudication adverse to
such director establishes that:

          -    his acts or omissions  were in bad faith or involved  intentional
               misconduct or a knowing violation of law;

          -    such  director  personally  gained a  financial  profit  or other
               advantage to which he was not legally entitled; or

          -    his  acts   violated   Section  719  of  the  New  York  Business
               Corporation Law.

         The provisions of KeySpan's certificate of incorporation are intended
to afford directors protection, and limit their potential liability, to the
fullest extent permitted by New York law. As a result of the inclusion of such
provisions, shareholders may be unable to recover monetary damages against
directors for actions taken by them that constitute negligence or gross
negligence or that are in violation of certain of their fiduciary duties. This
provision does not affect a director's responsibilities under any other laws,
such as the federal securities laws. In addition, KeySpan's certificate of
incorporation provides that it will indemnify its directors and officers to the
fullest extent permitted by New York law.

         KeySpan has obtained directors' and officers' insurance for its
directors and officers for specified liabilities.

Listing

         The outstanding shares of common stock are listed on the New York Stock
Exchange and the Pacific Stock Exchange and application will be made to list the
additional common stock offered under this prospectus on those exchanges.

Transfer agent and registrar

     The transfer  agent and  registrar  for the common stock is The Bank of New
York,  Shareholder  Services Dept.,  Church Street Station,  P.O. Box 11258, New
York, New York 10286-1258.

        Description of Stock Purchase Contracts and Stock Purchase Units


         KeySpan may issue stock purchase contracts, including contracts
obligating holders to purchase from KeySpan, and KeySpan to sell to the holders,
a specified number of shares of common stock at a future date or dates. The
price per share of common stock and the number of shares of common stock may be
fixed at the time the stock purchase contracts are issued or may be determined
by reference to a specific formula set forth in the stock purchase contracts.
The stock purchase contracts may be issued separately or as part of units
consisting of a stock purchase contract and beneficial interests in debt
securities or preferred stock of KeySpan, trust preferred securities of a trust
or debt obligations of third parties, including U.S. treasury securities,
securing the holders' obligations to purchase the common stock under the stock
purchase contracts. The stock purchase contracts may require KeySpan to make
periodic payments to the holders of the stock purchase units or vice versa, and
these payments may be unsecured or refunded on some basis. The stock purchase
contracts may require holders to secure their obligations under those contracts
in a specified manner.

         The applicable prospectus supplement will describe the terms of the
stock purchase contracts or stock purchase units, including, if applicable,
collateral or depositary arrangements, relating to the stock purchase contracts
or stock purchase units.









                    Description of Warrants and Warrant Units


         KeySpan may issue warrants, including debt warrants, which are warrants
to purchase debt securities, and equity warrants, which include warrants to
purchase common stock, preferred stock or depositary shares. KeySpan may issue
warrants independently of or together with any other securities, including as
part of a warrant unit, and warrants may be attached to or separate from those
securities.

         Each series of warrants will be issued under a separate warrant
agreement to be entered into between KeySpan and a warrant agent. The warrant
agent will act solely as KeySpan's agent in connection with a series of warrants
and will not assume any obligation or relationship of agency for or with holders
or beneficial owners of warrants. The following describes the general terms and
provisions of the warrants offered by this prospectus. The applicable prospectus
supplement will describe any other terms of the warrant and the applicable
warrant agreement. The warrant agreement for a particular series of warrants
will be filed as an exhibit to a document incorporated by reference in the
registration statement of which this prospectus forms a part.

         Each warrant unit will consist of a warrant under which the holder,
upon exercise, will purchase (a) a specified number of shares of common stock
and (b) any of a debt security, share of preferred stock or depositary share
relating to preferred stock.

Debt Warrants

         The applicable prospectus supplement will describe the terms of any
debt warrants, including the following:

          -    the title and aggregate number of the debt warrants;

          -    any offering price of the debt warrants;

          -    whether  the  debt  warrants  are  to be  issued  with  any  debt
               securities,  and, if so, the title,  total  principal  amount and
               terms;

          -    the  number of debt  warrants  and debt  securities  that will be
               separately transferable;

          -    any date on and after the debt warrants and debt  securities will
               be separately transferable;

          -    the title, total principal amount,  ranking and terms,  including
               subordination and conversion  provisions,  of the underlying debt
               securities  that  may be  purchased  upon  exercise  of the  debt
               warrants;

          -    the time or period when the debt  warrants are  exercisable,  the
               minimum or maximum amount of debt warrants which may be exercised
               at any one time,  and the final  date on which the debt  warrants
               may be exercised;

          -    the principal  amount of underlying  debt  securities that may be
               purchased  upon  exercise of each debt warrant and the price,  or
               the  manner of  determining  the  price,  at which the  principal
               amount may be purchased upon exercise;

          -    the terms of any right to redeem or call the debt warrants;

          -    any book-entry procedure information;

          -    any currency or currency  units in which the  offering  price and
               the exercise price are payable; and

          -    any other terms of the debt  warrants not  inconsistent  with the
               provisions of the debt warrant agreement.

Equity Warrants

         The applicable prospectus supplement will describe the terms of any
equity warrants, including the following:

          -    the title and aggregate number of the equity warrants;

          -    any offering price of the equity warrants;

          -    the  designation  and  terms  of any  preferred  shares  that are
               purchasable upon exercise of the equity warrants or that underlie
               depositary shares purchasable upon this exercise;

          -    if applicable,  the  designation and terms of the securities with
               which the equity warrants are issued and the number of the equity
               warrants issued with each security;

          -    if  applicable,  the date from and after the equity  warrants and
               any securities issued with them will be separately transferable;

          -    the  number  of  shares  of  common  stock,  preferred  stock  or
               depositary shares  purchasable upon exercise of an equity warrant
               and the price;

          -    the time or period when the equity  warrants are  exercisable and
               the final date on which the equity  warrants may be exercised and
               terms  regarding  any right of KeySpan to  accelerate  this final
               date;

          -    if  applicable,  the  minimum  or  maximum  amount of the  equity
               warrants exercisable at any one time;

          -    any currency or currency  units in which the  offering  price and
               the exercise price are payable;

          -    any applicable anti-dilution provisions of the equity warrants;

          -    any applicable redemption or call provisions; and

          -    any additional terms of the equity warrants not inconsistent with
               the provisions of the equity warrant agreement.

Warrant Units

         The applicable prospectus supplement will describe the specific terms
of any warrant units.









                  United States Federal Income Tax Consequences


         The following summary describes the material United States federal
income tax consequences of the purchase, ownership and disposition of debt
securities, trust preferred securities, preferred stock and common stock as of
the date of this prospectus. Except where noted, this summary deals only with
debt securities, trust preferred securities, preferred stock and common stock
purchased on original issue at their issue price and held as capital assets by
United States holders, and does not deal with special situations. For example,
this summary does not address:

          -    tax  consequences  to holders  who may be subject to special  tax
               treatment, such as dealers in securities or currencies, financial
               institutions, real estate investment trusts, regulated investment
               companies,  tax-exempt entities,  insurance companies, traders in
               securities  that  elect  to  use  a   mark-to-market   method  of
               accounting for their securities  holdings,  or persons liable for
               alternative minimum tax;

          -    tax  consequences  to  persons  holding  debt  securities,  trust
               preferred securities,  preferred stock or common stock as part of
               a  hedging,   integrated,   conversion   or   constructive   sale
               transaction or a straddle;

          -    tax  consequences  to United States  holders of debt  securities,
               trust preferred securities, preferred stock or common stock whose
               "functional currency" is not the U.S. dollar;

          -    alternative minimum tax consequences, if any; or

          -    any state, local or foreign tax consequences.

         The discussion below is based upon the provisions of the Internal
Revenue Code of 1986, as amended (the "Code"), and regulations, rulings and
judicial decisions as of the date of this prospectus. Those authorities may be
changed, perhaps retroactively, so as to result in United States federal income
tax consequences different from those discussed below. The discussion set forth
below also assumes that all debt securities issued under this prospectus
constitute debt for United States federal income tax purposes. If any debt
security does not constitute debt for United States federal income tax purposes,
the tax consequences of the ownership of that debt security could differ
materially from the tax consequences described herein. KeySpan will summarize
any special United States federal income tax considerations relevant to a
particular issue of debt securities, trust preferred securities, preferred stock
or common stock in the applicable prospectus supplement. KeySpan will also
summarize certain United States federal income tax consequences, if any,
applicable to any offering of depositary shares, stock purchase contracts, stock
purchase units, warrants or warrant units in the applicable prospectus
supplement.

         For the purposes of this summary, a "United States holder" means a
beneficial owner of the debt securities, trust preferred securities, preferred
stock or common stock offered in this prospectus that is:

          -    a citizen or resident of the United States;

          -    a corporation or partnership created or organized in or under the
               laws of the United  States or any  political  subdivision  of the
               United States;

          -    an estate the income of which is subject to United States federal
               income taxation regardless of its source; or

          -    a trust that (x) is subject to the primary supervision of a court
               within the United  States and one or more United  States  persons
               have the  authority to control all  substantial  decisions of the
               trust or (y) has a valid  election  in  effect  under  applicable
               United  States  Treasury  regulations  to be  treated as a United
               States person.

         A "non-United States holder" means a beneficial owner of the debt
securities, trust preferred securities, preferred stock or common stock that is
not a United States holder.

         If a partnership holds the debt securities, trust preferred securities,
preferred stock or common stock offered in this prospectus, the tax treatment of
a partner will generally depend upon the status of the partner and the
activities of the partnership. If you are a partner of a partnership holding the
offered debt securities, trust preferred securities, preferred stock or common
stock, you should consult your tax advisors.

         If you are considering the purchase of debt securities, trust preferred
securities, preferred stock or common stock, you should consult your own tax
advisors concerning the United States federal income tax consequences to you and
any consequences arising under the laws of any other taxing jurisdiction.

Debt securities

      Consequences to United States holders

         The following is a summary of certain United States federal income tax
consequences that will apply to you if you are a United States holder of debt
securities.

      Payments of interest

         Except as set forth below, interest on a debt security will generally
be taxable to you as ordinary income from domestic sources at the time it is
paid or accrued in accordance with your method of accounting for tax purposes.

      Original issue discount

         If you own debt securities issued with original issue discount ("OID"),
you will be subject to special tax accounting rules, as described in greater
detail below. In that case, you should be aware that you generally must include
OID in gross income in advance of the receipt of cash attributable to that
income. However, you generally will not be required to include separately in
income cash payments received on the debt securities, even if denominated as
interest, to the extent those payments do not constitute qualified stated
interest, as defined below. Notice will be given in the applicable prospectus
supplement when KeySpan determines that a particular debt security will be an
original issue discount debt security.

         A debt security with an issue price that is less than the "stated
redemption price at maturity" (the sum of all payments to be made on the debt
security other than "qualified stated interest") generally will be issued with
OID if that difference is at least 0.25% of the stated redemption price at
maturity multiplied by the number of complete years to maturity. The "issue
price" of each debt security in a particular offering will be the first price at
which a substantial amount of that particular offering is sold to the public.
The term "qualified stated interest" means stated interest that is
unconditionally payable in cash or in property, other than debt instruments of
the issuer, provided the interest to be paid meets all of the following
conditions:

          -    it is payable at least once per year;

          -    it is payable over the entire term of the debt security; and

          -    it is  payable  at a single  fixed  rate or,  subject  to certain
               conditions, based on one or more interest indices.

         KeySpan will give you notice in the applicable prospectus supplement
when it determines that a particular debt security will bear interest that is
not qualified stated interest.

         If you own a debt security issued with "de minimis" OID, which is
discount that is not OID because it is less than 0.25% of the stated redemption
price at maturity multiplied by the number of complete years to maturity, you
generally must include the de minimis OID in income at the time payments, other
than qualified stated interest, on the debt securities are made in proportion to
the amount paid. Any amount of de minimis OID that you have included in income
will be treated as capital gain.

         Certain of the debt securities may contain provisions permitting them
to be redeemed prior to their stated maturity at KeySpan's option and/or at your
option. OID debt securities containing those features may be subject to rules
that differ from the general rules discussed herein. If you are considering the
purchase of OID debt securities with those features, you should carefully
examine the applicable prospectus supplement and should consult your own tax
advisors with respect to those features since the tax consequences to you with
respect to OID will depend, in part, on the particular terms and features of the
debt securities.

         If you own OID debt securities with a maturity upon issuance of more
than one year you generally must include OID in income in advance of the receipt
of some or all of the related cash payments using the "constant yield method"
described in the following paragraph. This method takes into account the
compounding of interest. The accruals of OID on an OID debt security will
generally be less in the early years and more in the later years.

         The amount of OID that you must include in income if you are the
initial United States holder of an OID debt security is the sum of the "daily
portions" of OID with respect to the debt security for each day during the
taxable year or portion of the taxable year in which you held that debt security
("accrued OID"). The daily portion is determined by allocating to each day in
any "accrual period" a pro rata portion of the OID allocable to that accrual
period. The "accrual period" for an OID debt security may be of any length and
may vary in length over the term of the debt security, provided that each
accrual period is no longer than one year and each scheduled payment of
principal or interest occurs on the first day or the final day of an accrual
period. The amount of OID allocable to any accrual period is an amount equal to
the excess, if any, of:

          -    the debt security's  adjusted issue price at the beginning of the
               accrual period multiplied by its yield to maturity, determined on
               the basis of  compounding at the close of each accrual period and
               properly adjusted for the length of the accrual period, over

          -    the aggregate of all qualified  stated interest  allocable to the
               accrual period.

         OID allocable to a final accrual period is the difference between the
amount payable at maturity, other than a payment of qualified stated interest,
and the adjusted issue price at the beginning of the final accrual period. The
"adjusted issue price" of a debt security at the beginning of any accrual period
is equal to its issue price increased by the accrued OID for each prior accrual
period, determined without regard to the amortization of any acquisition or bond
premium, as described below, and reduced by any payments made on the debt
security (other than qualified stated interest) on or before the first day of
the accrual period. Under these rules, you will have to include in income
increasingly greater amounts of OID in successive accrual periods. KeySpan is
required to provide information returns stating the amount of OID accrued on
debt securities held of record by persons other than corporations and other
exempt holders.

         Floating rate debt securities are subject to special OID rules. In the
case of an OID debt security that is a floating rate debt security, both the
"yield to maturity" and "qualified stated interest" will be determined solely
for purposes of calculating the accrual of OID as though the debt security will
bear interest in all periods at a fixed rate generally equal to the rate that
would be applicable to interest payments on the debt security on its date of
issue or, in the case of certain floating rate debt securities, the rate that
reflects the yield to maturity that is reasonably expected for the debt
security. Additional rules may apply if

          -    the  interest on a floating  rate debt  security is based on more
               than one interest index; or

          -    the  principal  amount of the debt  security  is  indexed  in any
               manner.

         You may elect to treat all interest on any debt security as OID and
calculate the amount includible in gross income under the constant yield method
described above. For purposes of this election, interest includes stated
interest, acquisition discount, OID, de minimis OID, market discount, de minimis
market discount and unstated interest, as adjusted by any amortizable bond
premium or acquisition premium. You must make this election for the taxable year
in which you acquired the debt security, and you may not revoke the election
without the consent of the Internal Revenue Service (the "IRS"). You should
consult with your own tax advisors about this election.

      Short-term debt securities

         In the case of debt securities having a term of one year or less, all
payments, including all stated interest, will be included in the stated
redemption price at maturity and will not be qualified stated interest. As a
result, you will generally be taxed on the discount instead of stated interest.
The discount will be equal to the excess of the stated redemption price at
maturity over the issue price of a short-term debt security, unless you elect to
compute this discount using tax basis instead of issue price.

         In general, individual and certain other cash method United States
holders of short-term debt securities are not required to include accrued
discount in their income currently unless they elect to do so, but may be
required to include stated interest in income as the interest is received.
United States holders that report income for United States federal income tax
purposes on the accrual method and certain other United States holders are
required to accrue discount on short-term debt securities (as ordinary income)
on a straight-line basis, unless an election is made to accrue the discount
according to a constant yield method based on daily compounding. If you are not
required, and do not elect, to include discount in income currently, any gain
you realize on the sale, exchange or retirement of a short-term debt security
will generally be ordinary income to you to the extent of the discount accrued
by you through the date of sale, exchange or retirement. In addition, if you do
not elect to currently include accrued discount in income you may be required to
defer deductions for a portion of your interest expense with respect to any
indebtedness attributable to the short-term debt securities.

      Market discount

         If you purchase a debt security, other than an OID debt security, for
an amount that is less than its stated redemption price at maturity, or, in the
case of an OID debt security, its adjusted issue price, the amount of the
difference will be treated as "market discount" for United States federal income
tax purposes, unless that difference is less than a specified de minimis amount.
Under the market discount rules, you will be required to treat any payment,
other than qualified stated interest, on, or any gain on the sale, exchange,
retirement or other disposition of, a debt security as ordinary income to the
extent of the market discount that you have not previously included in income
and are treated as having accrued on the debt security at the time of its
payment or disposition. In addition, you may be required to defer, until the
maturity of the debt security or its earlier disposition in a taxable
transaction, the deduction of all or a portion of the interest expense on any
indebtedness attributable to the debt security.

         Any market discount will be considered to accrue ratably during the
period from the date of acquisition to the maturity date of the debt security,
unless you elect to accrue on a constant interest method. You may elect to
include market discount in income currently as it accrues, on either a ratable
or constant interest method, in which case the rule described above regarding
deferral of interest deductions will not apply. Your election to include market
discount in income currently, once made, applies to all market discount
obligations acquired by you on or after the first taxable year to which your
election applies and may not be revoked without the consent of the IRS. You
should consult your own tax advisor before making this election.

      Acquisition premium, amortizable bond premium

         If you purchase an OID debt security for an amount that is greater than
its adjusted issue price but equal to or less than the sum of all amounts
payable on the debt security after the purchase date other than payments of
qualified stated interest, you will be considered to have purchased that debt
security at an "acquisition premium." Under the acquisition premium rules, the
amount of OID that you must include in gross income with respect to the debt
security for any taxable year will be reduced by the portion of the acquisition
premium properly allocable to that year.

         If you purchase a debt security (including an OID debt security) for an
amount in excess of the sum of all amounts payable on the debt security after
the purchase date other than qualified stated interest, you will be considered
to have purchased the debt security at a "premium" and, if it is an OID debt
security, you will not be required to include any OID in income. You generally
may elect to amortize the premium over the remaining term of the debt security
on a constant yield method as an offset to interest when includible in income
under your regular accounting method. Special rules limit the amortization of
premium in the case of convertible debt securities. In the case of instruments
that provide for alternative payment schedules, bond premium is calculated by
assuming that (a) you will exercise or not exercise options in a manner that
maximizes your yield, and (b) KeySpan will exercise or not exercise options in a
manner that minimizes your yield (except that KeySpan will be assumed to
exercise call options in a manner that maximizes your yield). If you do not
elect to amortize bond premium, that premium will decrease the gain or increase
the loss you would otherwise recognize on disposition of the debt security. Your
election to amortize premium on a constant yield method will also apply to all
debt obligations held or subsequently acquired by you on or after the first day
of the first taxable year to which the election applies. You may not revoke the
election without the consent of the IRS. You should consult your own tax advisor
before making this election.

      Sale, exchange and retirement of debt securities

         Your tax basis in a debt security will, in general, be your cost for
that debt security, increased by OID, market discount or any discount with
respect to a short-term debt security that you previously included in income,
and reduced by any amortized premium and any cash payments on the debt security
other than qualified stated interest. Upon the sale, exchange, retirement or
other disposition of a debt security, you will recognize gain or loss equal to
the difference between the amount you realize upon the sale, exchange,
retirement or other disposition (less an amount equal to any accrued qualified
stated interest, which will be taxed as a payment of interest for federal income
tax purposes) and the adjusted tax basis of the debt security. Except as
described above with respect to certain short-term debt securities or with
respect to market discount, or as described below with respect to foreign
currency debt securities or with respect to contingent payment debt securities,
that gain or loss will be capital gain or loss. Capital gains of individuals
derived in respect of capital assets held for more than one year are eligible
for reduced rates of taxation. The deductibility of capital losses is subject to
limitations.

     Extendible  debt  securities,  renewable  debt  securities  and reset  debt
     securities

         If so specified in an applicable prospectus supplement relating to a
debt security, KeySpan may have the option to extend the maturity of a debt
security. In addition, KeySpan may have the option to reset the interest rate,
the spread or the spread multiplier.

         The United States federal income tax treatment of a debt security with
respect to which such an option has been exercised is unclear and will depend,
in part, on the terms established for such debt securities by KeySpan pursuant
to the exercise of the option. You may be treated for United States federal
income tax purposes as having exchanged your debt securities for new debt
securities with revised terms. If this is the case, you would realize gain or
loss equal to the difference between the issue price of the new debt securities
and your tax basis in the old debt securities, which would be recognized subject
to certain possible exceptions. Furthermore, the new debt securities might be
subject to withholding, backup withholding and/or information reporting and
might be deemed to be issued with OID.

         Even though federal income tax on the deemed exchange may be imposed on
you, you would not receive any cash until the maturity or an earlier redemption
of the new debt securities, except for any current interest payments.

         If the exercise of the option is not treated as an exchange of old debt
securities for new debt securities, you will not recognize gain or loss as a
result of such exchange.

         The presence of these options may also affect the calculation of OID,
among other things. Solely for purposes of the accrual of OID, if KeySpan issues
a debt security and has an option or combination of options to extend the term
of the debt security, KeySpan will be presumed to exercise such option or
options in a manner that minimizes the yield on the debt security. Conversely,
if you are treated as having a put option, such an option will be presumed to be
exercised in a manner that maximizes the yield on the debt security. If KeySpan
exercises such option or options to extend the term of the debt security, or
your option to put does not occur (contrary to the assumptions made), then
solely for purposes of the accrual of OID, the debt security will be treated as
reissued on the date of the change in circumstances for an amount equal to its
adjusted issue price on that date.

         You should carefully examine the applicable prospectus supplement and
should consult your own tax advisor regarding the United States federal income
tax consequences of the holding and disposition of such debt securities.

      Foreign currency debt securities

         Payments of interest

         If you receive interest payments made in a foreign currency and you use
the cash basis method of accounting, you will be required to include in income
the U.S. dollar value of the amount received, determined by translating the
foreign currency received at the "spot rate" for such foreign currency on the
date such payment is received regardless of whether the payment is in fact
converted into U.S. dollars. You will not recognize exchange gain or loss with
respect to the receipt of such payment.

         If you use the accrual method of accounting, you may determine the
amount of income recognized with respect to such interest in accordance with
either of two methods. Under the first method, you will be required to include
in income for each taxable year the U.S. dollar value of the interest that has
accrued during such year, determined by translating such interest at the average
rate of exchange for the period or periods during which such interest accrued.
Under the second method, you may elect to translate interest income at the spot
rate on:

          -    the last day of the accrual period;

          -    the last day of the taxable year if the accrual period  straddles
               your taxable year; or

          -    the date the interest  payment is received if such date is within
               five days of the end of the accrual period.

         Upon receipt of an interest payment on such debt security (including,
upon the sale of such debt security, the receipt of proceeds which include
amounts attributable to accrued interest previously included in income), you
will recognize ordinary gain or loss in an amount equal to the difference
between the U.S. dollar value of such payment (determined by translating the
foreign currency received at the spot rate for such foreign currency on the date
such payment is received) and the U.S. dollar value of the interest income you
previously included in income with respect to such payment.

         Original issue discount

         OID on a debt security that is also a foreign currency debt security
will be determined for any accrual period in the applicable foreign currency and
then translated into U.S. dollars, in the same manner as interest income accrued
by a holder on the accrual basis, as described above. You will recognize
exchange gain or loss when OID is paid (including, upon the sale of such debt
security, the receipt of proceeds which include amounts attributable to OID
previously included in income) to the extent of the difference between the U.S.
dollar value of such payment (determined by translating the foreign currency
received at the spot rate for such foreign currency on the date such payment is
received) and the U.S. dollar value of the accrued OID (determined in the same
manner as for accrued interest). For these purposes, all receipts on a debt
security will be viewed:

          -    first, as the receipt of any stated  interest  payment called for
               under the terms of the debt security;

          -    second,  as  receipts  of  previously  accrued OID (to the extent
               thereof),  with payments considered made for the earliest accrual
               periods first; and

          -    third, as the receipt of principal.

         Market discount and bond premium

         The amount of market discount on foreign currency debt securities
includible in income will generally be determined by translating the market
discount determined in the foreign currency into U.S. dollars at the spot rate
on the date the foreign currency debt security is retired or otherwise disposed
of. If you have elected to accrue market discount currently, then the amount
which accrues is determined in the foreign currency and then translated into
U.S. dollars on the basis of the average exchange rate in effect during such
accrual period. You will recognize exchange gain or loss with respect to market
discount which is accrued currently using the approach applicable to the accrual
of interest income as described above.

         Bond premium on a foreign currency debt security will be computed in
the applicable foreign currency. If you have elected to amortize the premium,
the amortizable bond premium will reduce interest income in the applicable
foreign currency. At the time bond premium is amortized, exchange gain or loss,
which is generally ordinary gain or loss, will be realized based on the
difference between spot rates at such time and the time of acquisition of the
foreign currency debt security.

         If you elect not to amortize bond premium, you must translate the bond
premium computed in the foreign currency into U.S. dollars at the spot rate on
the maturity date and such bond premium will constitute a capital loss which may
be offset or eliminated by exchange gain.

         Sale, exchange or retirement

         Your tax basis in a foreign currency debt security will be the U.S.
dollar value of the foreign currency amount paid for such foreign currency debt
security determined at the time of your purchase. If you purchased the foreign
currency debt security with previously owned foreign currency, you will
recognize exchange gain or loss at the time of the purchase attributable to the
difference at the time of purchase, if any, between the fair market value of the
debt security in U.S. dollars on the date of purchase and your tax basis in the
foreign currency. Such gain or loss will be ordinary income or loss.

         For purposes of determining the amount of any gain or loss you
recognize on the sale, exchange, retirement or other disposition of a foreign
currency debt security, the amount realized on such sale, exchange, retirement
or other disposition generally will be the U.S. dollar value of the amount
realized in foreign currency (less an amount equal to any accrued qualified
stated interest, which will be treated as a payment of interest for federal
income tax purposes) determined at the time of the sale, exchange, retirement or
other disposition.

         However, regulations issued under Section 988 of the Code provide a
special rule for purchases and sales of foreign currency debt securities traded
on an established securities market by a cash method taxpayer, under which
foreign currency paid or received is translated into U.S. dollars at the spot
rate on the settlement date of the purchase or sale. An accrual method taxpayer
may elect the same treatment with respect to the purchase and sale of foreign
currency debt securities traded on an established securities market, provided
that the election is applied consistently. This election cannot be changed
without the consent of the IRS.

         You may also recognize exchange gain or loss attributable to the
movement in exchange rates between the time of purchase and the time of
disposition (including the sale, exchange, retirement or other disposition) of a
foreign currency debt security. Such gain or loss will be treated as ordinary
income or loss. The realization of such gain or loss will be limited to the
amount of overall gain or loss realized on the disposition of a foreign currency
debt security.

         If a foreign currency debt security is denominated in one of certain
hyperinflationary currencies, generally:

          -    exchange gain or loss would be realized with respect to movements
               in the  exchange  rate  between  the  beginning  and  end of each
               taxable year (or such shorter period) the debt security was held,
               and

          -    such  exchange  gain or loss would be treated as an  addition  or
               offset,  respectively,  to the accrued interest income on, and an
               adjustment  to the  holder's  tax basis in, the foreign  currency
               debt security.

         Your tax basis in the foreign currency received as interest on a
foreign currency debt security will be the U.S. dollar value thereof at the spot
rate in effect on the date the foreign currency is includible in income. Your
tax basis in foreign currency received on the sale, exchange, retirement or
other disposition of a foreign currency debt security will be equal to the U.S.
dollar value of the foreign currency, determined at the time of the sale,
exchange, retirement or other disposition. As discussed above, if the foreign
currency debt securities are traded on an established securities market, a cash
basis United States holder (or, upon election, an accrual basis United States
holder) will determine the U.S. dollar value of the foreign currency by
translating the foreign currency received at the spot rate of exchange on the
settlement date of the sale, exchange, retirement or other disposition.
Accordingly, in such case, no foreign currency gain or loss will result from
currency fluctuations between the trade date and settlement date of a sale,
exchange, retirement or other disposition. Any gain or loss recognized by you on
a sale, exchange, retirement or other disposition of foreign currency will be
ordinary income or loss and will not be treated as interest income or expense,
except to the extent provided in United States Treasury regulations or
administrative pronouncements of the IRS.

         Dual currency debt securities

         If so specified in an applicable prospectus supplement relating to a
foreign currency debt security, KeySpan may have the option to make all payments
of principal and interest scheduled after the exercise of such option in a
currency other than the specified currency. The United States federal income tax
treatment of dual currency debt securities is uncertain. United States Treasury
regulations currently in effect do not address the tax treatment of dual
currency debt securities.

         An IRS announcement states that the IRS is considering issuing proposed
regulations that would:

          -    apply  the   principles   contained  in   regulations   governing
               contingent  debt  instruments to dual currency debt securities in
               the  "predominant  currency" of the dual currency debt securities
               and

          -    apply the rules discussed above with respect to foreign  currency
               debt  securities  with OID for the  translation  of interest  and
               principal into U.S. dollars.

         The IRS states that these concepts are still under consideration.
Persons considering the purchase of dual currency debt securities should
carefully examine the applicable prospectus supplement and should consult their
own tax advisors regarding the United States federal income tax consequences of
the ownership and disposition of such debt securities.

         If KeySpan exercises such an option, you may be considered to have
exchanged your debt security denominated in the specified currency for a debt
security denominated in the optional payment currency. If the exercise is
treated as a taxable exchange, you will recognize gain or loss, if any, equal to
the difference between your basis in the debt security denominated in the
specified currency and the value of the debt security denominated in the
optional payment currency. If the exercise of the option is not treated as an
exchange, you will not recognize gain or loss and your basis in the debt
security will be unchanged.

      Contingent payment debt securities

         The OID regulations contain special rules for determining the timing
and amount of OID to be accrued with respect to certain debt securities
providing for one or more contingent payments. Under these rules, you will
accrue OID each year based on the "comparable yield" of the debt securities. The
comparable yield of the debt securities will generally be the rate at which
KeySpan would issue a fixed rate debt instrument with terms and conditions
similar to the debt securities.

         KeySpan is required to provide the comparable yield to you and, solely
for tax purposes, is also required to provide a projected payment schedule that
includes the actual interest payments on the debt securities and estimates the
amount and timing of contingent payments on the debt securities. Pursuant to the
terms of the subordinated debt indenture, you will be bound by KeySpan's
determination. For United States federal income tax purposes, you must use the
comparable yield and the schedule of projected payments in determining your
interest accruals, and the adjustments thereto described below, in respect of
the contingent payment debt securities. KeySpan will give notice in the
applicable prospectus supplement when it determines that a particular debt
security will be treated as contingent debt.

         The amount of OID on a contingent payment debt security for each
accrual period is determined by multiplying the comparable yield of the
contingent payment debt security (adjusted for the length of the accrual period)
by the debt security's adjusted issue price at the beginning of the accrual
period (determined in accordance with the rules set forth in the OID regulations
relating to contingent payment debt instruments). The amount of OID so
determined will then be allocated on a ratable basis to each day in the accrual
period that you hold the contingent payment debt security.

         If the actual payments made on the contingent payment debt securities
in a taxable year differ from the projected contingent payments, adjustments
will be made for such differences. A positive adjustment, for the amount by
which an actual payment exceeds a projected contingent payment, will be treated
as additional interest. A negative adjustment will:

          -    first,  reduce the amount of  interest  required  in the  current
               year;

          -    second,  any  negative  adjustments  that  exceed  the  amount of
               interest  accrued in the current year will be treated as ordinary
               loss to the extent that your total interest inclusions exceed the
               total amount of net negative adjustments treated as ordinary loss
               in prior taxable years; and

          -    third, any excess negative adjustments will be carried forward to
               offset future income or the amount realized on disposition.

         Gain on the sale, exchange or retirement of a contingent payment debt
security generally will be treated as ordinary income. Loss from the disposition
of a contingent payment debt security will be treated as ordinary loss to the
extent of your prior net interest inclusions (reduced by the total net negative
adjustments previously allowed as an ordinary loss). Any loss in excess of such
amount will be treated as capital loss.

         For special treatment of foreign currency debt securities that are also
contingent payment debt securities, see the applicable prospectus supplement.

         The rules regarding contingent payment debt securities are complex. If
you are considering the purchase of debt securities providing for one or more
contingent payments, you should carefully examine the applicable prospectus
supplement and consult your own tax advisors regarding the United States federal
income tax consequences of the ownership and disposition of such debt
securities.

      Consequences to non-United States holders

         The following is a summary of certain United States federal income tax
consequences that will apply to you if you are a non-United States holder of
debt securities.

      United States federal withholding tax

         The 30% United States federal withholding tax will generally not apply
to any payment of principal or interest, including OID, on debt securities
provided that:

          -    you do not  actually  or  constructively  own  10% or more of the
               total  combined  voting  power of all  classes of KeySpan  voting
               stock  within  the  meaning  of the  Code and the  United  States
               Treasury regulations;

          -    you are not a controlled  foreign  corporation that is related to
               KeySpan through stock ownership;

          -    you  are  not a bank  whose  receipt  of  interest  on  the  debt
               securities is described in Section 881(c)(3)(A) of the Code; and

          -    either  (a) you  provide  your  name and  address  on an IRS Form
               W-8BEN (or other applicable  form), and certify,  under penalties
               of perjury,  that you are not a United  States  person or (b) you
               hold your notes through certain foreign  intermediaries,  and you
               satisfy  the  certification  requirements  of  applicable  United
               States Treasury regulations.

         Special certification rules apply to certain non-United States holders
that are entities rather than individuals. If you cannot satisfy the
requirements described above, payments of interest, including OID, made to you
will be subject to the 30% United States federal withholding tax, unless you
provide KeySpan with a properly executed:

          -    IRS Form W-8BEN (or other  applicable form) claiming an exemption
               from,  or  reduction  in,  withholding  under the  benefit  of an
               applicable income tax treaty; or

          -    IRS Form W-8ECI stating that interest paid on the debt securities
               is not  subject to  withholding  tax  because  it is  effectively
               connected  with your conduct of a trade or business in the United
               States as discussed  below under "United  States  federal  income
               tax".

         The 30% United States federal withholding tax will generally not apply
to any gain that you realize on the sale, exchange, retirement or other
disposition of debt securities.

      United States federal income tax

         If you are engaged in a trade or business in the United States and
interest, including OID, on the debt securities is effectively connected with
the conduct of that trade or business, you will be subject to United States
federal income tax on that interest, including OID, on a net income basis
(although exempt from the 30% withholding tax, provided the certification
requirements discussed above are satisfied) in the same manner as if you were a
United States holder. In addition, if you are a foreign corporation, you may be
subject to a branch profits tax equal to 30% (or lower applicable treaty rate)
of your earnings and profits for the taxable year, subject to adjustments.

         You will generally not be subject to United States federal income tax
on the disposition of a debt security unless:

          -    the gain is effectively connected with your conduct of a trade or
               business in the United States; or

          -    you are an individual who is present in the United States for 183
               days or more in the taxable year of that disposition, and certain
               other conditions are met.

         Special rules may apply to some non-United States holders, such as
"controlled foreign corporations", "passive foreign investment companies",
"foreign personal holdings companies", certain United States expatriates and
corporations that accumulate earnings to avoid United States federal income tax,
that are subject to special treatment under the Code. These entities should
consult their own tax advisors to determine the United States federal, state,
local and other tax consequences that may be relevant to them.

      United States federal estate tax

         Your estate will not be subject to United States federal estate tax on
debt securities beneficially owned by you at the time of your death, provided
that

          -    you do not own 10% or more of the total combined  voting power of
               all  classes of KeySpan  voting  stock  within the meaning of the
               Code and United States Treasury regulations and

          -    interest  on  those  debt  securities  would  not have  been,  if
               received at the time of your death,  effectively  connected  with
               the conduct by you of a trade or business in the United States.

      Information reporting and backup withholding

      United States holders

         In general, information reporting requirements will apply to certain
payments of principal and interest, including OID, paid on debt securities and
to the proceeds of sale of a debt security made to you (unless you are an exempt
recipient such as a corporation). A backup withholding tax will apply to such
payments if you fail to provide a taxpayer identification number or
certification of exempt status, or fail to report in full dividend and interest
income.

      Non-United States holders

         In general, no information reporting or backup withholding will be
required regarding payments that KeySpan makes to you provided that it does not
have actual knowledge that you are a United States person and it has received
from you the certification described above in the first sentence under
"Consequences to non-United States holders--United States federal withholding
tax."

         In addition, no information reporting or backup withholding will be
required regarding the proceeds of the sale of a debt security made within the
United States or conducted through certain United States-related financial
intermediaries, if:

          -    the payor receives the certification described above and does not
               have actual knowledge that you are a United States person; or

          -    you otherwise establish an exemption.

         Any amounts withheld under the backup withholding rules will be allowed
as a refund or a credit against your United States federal income tax liability
provided the required information is furnished to the IRS.

Trust preferred securities

      Classification of the trusts

         KeySpan intends to take the position that each trust will be classified
as a grantor trust for United States federal income tax purposes and not as an
association taxable as a corporation. As a condition to the issuance of the
subordinated debt securities, Simpson Thacher & Bartlett, special tax counsel to
KeySpan, will deliver an opinion that under current law and assuming full
compliance with the terms of the trust's amended and restated declaration, and
based upon certain facts and assumptions contained in such opinion, the trust
will be classified as a grantor trust for United States federal income tax
purposes. As a result, for United States federal income tax purposes, you
generally will be treated as owning an undivided beneficial ownership interest
in the subordinated debt securities. Thus, you will be required to include in
your gross income your pro rata share of the interest income or OID that is paid
or accrued on the subordinated debt securities. See "Consequences to United
States holders--Interest income and original issue discount" below.

      Classification of the subordinated debt securities

         KeySpan, the trust and you (by your acceptance of a beneficial
ownership interest in a trust preferred security) will agree to treat the
subordinated debt securities as indebtedness for all United States tax purposes.
As a condition to the issuance of the subordinated debt securities, Simpson
Thacher & Bartlett, special tax counsel to KeySpan, will deliver an opinion that
under current law, and based upon certain facts and assumptions contained in
such opinion, the subordinated debt securities will be classified as
indebtedness for United States federal income tax purposes.

      Consequences to United States holders

      Interest income and original issue discount

         KeySpan anticipates that the subordinated debt securities will not be
issued with an issue price that is less than their stated redemption price at
maturity. In this case, subject to the discussion below, the subordinated debt
securities will not be subject to the special OID rules, at least upon initial
issuance, so that you will generally be taxed on the stated interest on the
subordinated debt securities as ordinary income at the time it is paid or
accrued in accordance with your regular method of tax accounting.

         If, however, KeySpan exercises its right to defer payments of interest
on the subordinated debt securities, the subordinated debt securities will
become OID instruments at such time. In such case, you will be subject to the
special OID rules described below. Once the subordinated debt securities become
OID instruments, they will be taxed as OID instruments for as long as they
remain outstanding.

         Under the OID economic accrual rules, the following occurs:

          -    regardless  of your  method of  accounting,  you would  accrue an
               amount of interest income each year that  approximates the stated
               interest  payments called for under the terms of the subordinated
               debt securities  using the  constant-yield-to-maturity  method of
               accrual described in Section 1272 of the Code;

          -    the  actual  cash   payments  of  interest  you  receive  on  the
               subordinated debt securities would not be reported  separately as
               taxable income;

          -    any amount of OID included in your gross  income  (whether or not
               during a deferral  period)  with  respect to the trust  preferred
               securities  would increase your tax basis in such trust preferred
               securities; and

          -    the amount of  distributions  that you receive in respect of such
               accrued OID would  reduce your tax basis in such trust  preferred
               securities.

         The United States Treasury regulations dealing with OID and the
deferral of interest payments have not yet been addressed in any rulings or
other interpretations by the IRS. It is possible that the IRS could assert that
the subordinated debt securities were issued initially with OID merely because
of KeySpan's right to defer payments of interest. If the IRS were successful in
this regard, you would be subject to the special OID rules described above
regardless of whether KeySpan exercises its option to defer payments of interest
on such subordinated debt securities.

         If you are a corporate holder of trust preferred securities, you will
not be entitled to a dividends received deduction with respect to any income you
recognize with respect to the trust preferred securities.

      Distribution of subordinated debt securities or cash

         As described under the caption "Description of the Trust Preferred
Securities--Distribution of the subordinated debt securities", the subordinated
debt securities held by the trust may be distributed to you in exchange for your
trust preferred securities when the trust is dissolved. Under current law,
except as described below, this type of distribution from a grantor trust would
not be taxable. Upon a distribution, you will receive your pro rata share of the
subordinated debt securities previously held indirectly through the trust. Your
holding period and aggregate tax basis in the subordinated debt securities will
equal the holding period and aggregate tax basis that you had in your trust
preferred securities before the distribution. If, however, the trust would be
required to pay United States federal income tax relating to income accrued or
received on the subordinated debt securities, a tax event will occur. See
"Description of the Trust Preferred Securities--Special event redemption". If
KeySpan elects to distribute the subordinated debt securities to you at this
time, the distribution would be taxable to the trust and to you.

         If you receive subordinated debt securities in exchange for your trust
preferred securities, you would accrue interest in respect of the subordinated
debt securities received from the trust in the manner described above under
"--Interest income and original issue discount."

         In certain circumstances described above under the captions
"Description of the Trust Preferred Securities--Redemption" and "Description of
the Trust Preferred Securities--Special event redemption", KeySpan may redeem
the subordinated debt securities, in whole or in part, and the trust will use
the cash it receives upon the redemption to redeem trust securities having an
aggregate liquidation amount equal to the aggregate principal amount of the
subordinated debt securities so redeemed. The distribution of cash to holders of
trust preferred securities would be taxable as described below under "--Sales of
trust preferred securities or redemption of subordinated debt securities."

     Sales of trust  preferred  securities or redemption  of  subordinated  debt
     securities

         If you sell your trust preferred securities or receive cash upon
redemption of the subordinated debt securities, you will recognize gain or loss
equal to the difference between:

          -    your  amount  realized  on the sale or  redemption  of the  trust
               preferred  securities or subordinated  debt  securities  (less an
               amount equal to any accrued but unpaid qualified stated interest,
               which will be treated as a payment of interest for federal income
               tax purposes); and

          -    your  adjusted tax basis in your trust  preferred  securities  or
               subordinated debt securities sold or redeemed.

         Your gain or loss will be a capital gain or loss, provided that you
held the trust preferred securities or junor subordinated debt securities as a
capital asset. The gain or loss will generally be a long-term capital gain or
loss if you have held your trust preferred securities or subordinated debt
securities for more than one year. Long-term capital gains of individual derived
with respect to capital assets held for more than one year are currently subject
to tax at a maximum rate of 20%. The deductibility of capital losses is subject
to limitations.

      Consequences to non-United States holders

         The following discussion only applies to you if you are a non-United
States holder. As discussed above, the trust preferred securities will be
treated by the parties as evidence of undivided beneficial ownership interests
in the subordinated debt securities. See above under "--Classification of the
trusts". The following discussion assumes that the subordinated debt securities
will be treated as indebtedness for all United States tax purposes.

      United States federal withholding tax

         The 30% United States federal withholding tax will generally not apply
to any payment of principal or interest, including OID, on the trust preferred
securities (or the subordinated debt securities) provided that:

          -    you do not  actually  or  constructively  own  10% or more of the
               total  combined  voting  power of all  classes of KeySpan  voting
               stock  within  the  meaning  of the  Code and the  United  States
               Treasury regulations;

          -    you are not a controlled  foreign  corporation that is related to
               KeySpan through stock ownership;

          -    you  are  not a bank  whose  receipt  of  interest  on the  trust
               preferred  securities (or the  subordinated  debt  securities) is
               described in Section 881(c)(3)(A) of the Code; and

          -    either  (a) you  provide  your  name and  address  on an IRS Form
               W-8BEN (or other applicable  form), and certify,  under penalties
               of perjury,  that you are not a United States person,  or (b) you
               hold  your  trust  preferred  securities  (or  subordinated  debt
               securities)  through  certain  foreign  intermediaries,  and  you
               satisfy  the  certification  requirements  of  applicable  United
               States Treasury regulations.

         Special certification rules apply to certain non-United States holders
that are entities rather than individuals. If you cannot satisfy the
requirements described above, payments of interest, including OID, made to you
will be subject to the 30% United States federal withholding tax, unless you
provide KeySpan with a properly executed

          -    IRS Form W-8BEN (or other  applicable form) claiming an exemption
               from,  or  reduction  in,  withholding  under the  benefit  of an
               applicable income tax treaty; or

          -    IRS Form W-8ECI stating that interest paid on the trust preferred
               securities (or the  subordinated  debt securities) is not subject
               to withholding tax because it is effectively  connected with your
               conduct of a trade or business in the United  States as discussed
               below under "United States federal income tax."

         The 30% United States federal withholding tax will generally not apply
to any gain that you realize on the sale, exchange, retirement or other
disposition of trust preferred securities or subordinated debt securities.

      United States federal income tax

         If you are engaged in a trade or business in the United States and
interest, including OID, on the trust preferred securities (or the subordinated
debt securities) is effectively connected with the conduct of that trade or
business, you will be subject to United States federal income tax on that
interest, including OID, on a net income basis (although exempt from the 30%
withholding tax, provided the certification requirements discussed above are
satisfied) in the same manner as if you were a United States holder. In
addition, if you are a foreign corporation, you may be subject to a branch
profits tax equal to 30% (or lower applicable treaty rate) of your earnings and
profits for the taxable year, subject to adjustments.

         Any gain realized on the disposition of a trust preferred security (or
a subordinated debt security) generally will not be subject to United States
federal income tax unless:

          -    that gain is effectively connected with the conduct of a trade or
               business by you in the United States; or

          -    you are an individual who is present in the United States for 183
               days or more in the taxable year of that disposition, and certain
               other conditions are met.

         Special rules may apply to some non-United States holders, such as
"controlled foreign corporations", "passive foreign investment companies",
"foreign personal holding companies", certain United States expatriates and
corporations that accumulate earnings to avoid United States federal income tax,
that are subject to special treatment under the Code. These entities should
consult their own tax advisors to determine the United States federal, state,
local, and other tax consequences that may be relevant to them.

      United States federal estate tax

         Your estate will not be subject to United States federal estate tax on
the trust preferred securities (or the subordinated debt securities)
beneficially owned by you at the time of your death, provided that:

          -    you do not own 10% or more of the total combined  voting power of
               all  classes of KeySpan  voting  stock  within the meaning of the
               Code and United States Treasury regulations; and

          -    interest on those trust  preferred  securities  (or  subordinated
               debt securities)  would not have been, if received at the time of
               your death,  effectively  connected  with the conduct by you of a
               trade or business in the United States.

      Information reporting and backup withholding

      United States holders

         In general, information reporting requirements will apply to certain
payments of principal and interest, including OID, paid on the trust preferred
securities (or the subordinated debt securities) and to the proceeds of the sale
of trust preferred securities (or subordinated debt securities) made to you
(unless you are an exempt recipient such as a corporation). A backup withholding
tax will apply to such payments if you fail to provide a taxpayer identification
number or certification of exempt status, or fail to report in full dividend and
interest income.

      Non-United States holders

         In general, no information reporting or backup withholding will be
required regarding payments on the trust preferred securities (or the
subordinated debt securities) that KeySpan makes to you provided that it does
not have actual knowledge that you are a United States person and it has
received from you the certification described above in the first sentence under
"Consequences to non-United States holders--United States federal withholding
tax."

         In addition, no information reporting or backup withholding will be
required regarding the proceeds of the sale of trust preferred securities (or
subordinated debt securities) made within the United States or conducted through
certain United States-related financial intermediaries if:

          -    the payor receives the certification described above and does not
               have actual knowledge that you are a United States person; or

          -    you otherwise establish an exemption.

         Any amounts withheld under the backup withholding rules will be allowed
as a refund or a credit against your United States federal income tax liability
provided the required information is furnished to the IRS.

      Possible tax law changes

         Legislation proposed on January 24, 2002 contains a provision that
generally would deny the interest deduction for interest paid or accrued on debt
instruments that are not included as liabilities in the certified annual report
of the issuer. This provision is proposed to be effective for instruments issued
on or after the date of enactment of such legislation. There can be no assurance
that the proposed legislation, future legislative proposals or any final
legislation will not adversely affect the ability of KeySpan to deduct interest
on the subordinated debt securities or otherwise affect the tax treatment of
KeySpan or the investors in the trust preferred securities as described in this
registration statement. Such a change could give rise to a tax event, which
would permit KeySpan to redeem the subordinated debt securities. Such redemption
would cause a mandatory redemption of the trust preferred securities and would
constitute a taxable event as described above under "-- Consequences to United
States holders--Sales of trust preferred securities or redemption of
subordinated debt securities." See also "Description of the Trust Preferred
Securities--Special event redemption" in this registration statement.

Common and Preferred Stock

      Consequences to United States holders

         The consequences of the purchase, ownership or disposition of KeySpan
stock depend on a number of factors including:

          -    the term of the stock;

          -    any put or call option or redemption  provisions  with respect to
               the stock;

          -    any  conversion  or exchange  features with respect to the stock;
               and

          -    the price at which the stock is sold.

         United States holders should carefully examine the applicable
prospectus supplement regarding the material United States federal income tax
consequences, if any, of the ownership and disposition of stock with such terms.

      Consequences to non-United States holders

      Dividends

         In general, dividends paid to you (including any deemed dividends that
may arise from the excess of the redemption price over the issue price or
certain adjustments to the conversion ratio of convertible instruments) will be
subject to withholding of United States federal income tax at a 30% rate or a
lower rate if so specified by an applicable income tax treaty. However,
dividends that are effectively connected with your conduct of a trade or
business within the United States and, where a tax treaty applies, are
attributable to a United States permanent establishment, are not subject to the
withholding tax. Instead, these dividends are subject to United States federal
income tax on a net income basis at applicable graduated individual or corporate
rates. You must comply with certification and disclosure requirements in order
for effectively connected income to be exempt from withholding. If you are a
foreign corporation, any effectively connected dividends you receive may also be
subject to an additional branch profits tax at a 30% rate or a lower rate if so
specified by an applicable income tax treaty.

         A non-United States holder of common or preferred stock who wishes to
claim the benefit of an applicable treaty rate, and avoid backup withholding as
discussed below, will be required to satisfy the certification requirements of
applicable United States Treasury regulations. Special rules apply to claims for
treaty benefits made by non-United States persons that are entities rather than
individuals.

         If you are eligible for a reduced rate of United States withholding tax
pursuant to an income tax treaty, you may obtain a refund of any excess amounts
withheld by filing an appropriate claim for refund with the IRS.

      Gain on disposition of common or preferred stock

         You generally will not be subject to United States federal income tax
with respect to gain recognized on a sale or other disposition of common or
preferred stock unless:

          -    the gain is effectively connected with your conduct of a trade or
               business in the United States,  and, where a tax treaty  applies,
               is attributable to a United States permanent establishment;

          -    you are an individual  holding the common or preferred stock as a
               capital  asset and are  present in the  United  States for 183 or
               more days in the  taxable  year of the sale or other  disposition
               and certain other conditions are met; or

          -    KeySpan is or has been a "United  States  real  property  holding
               corporation" for United States federal income tax purposes.

         If you are an individual non-United States holder described in the
first of the three clauses above, you will be subject to United States federal
income tax on the net gain derived from the sale. If you are an individual
non-United States holder described in the second clause above, you will be
subject to a flat 30% United States federal income tax on the gain derived from
the sale, which may be offset by United States source capital losses, even
though you are not considered a resident of the United States. If you are a
non-United States holder that is a foreign corporation and you are described in
the first clause above, you will be subject to tax on your gain under regular
graduated United States federal income tax rates and, in addition, may be
subject to a branch profits tax at a 30% rate or a lower rate if so specified by
an applicable income tax treaty.

         KeySpan believes that it is currently a "United States real property
holding corporation" for United States federal income tax purposes. So long as
the common or preferred stock sold or otherwise disposed of is "regularly traded
on an established securities market", however, only a non-United States holder
who holds or held (at any time during the shorter of the five-year period
preceding the date of disposition or the holder's holding period) more than 5%
of such class of stock will be subject to United States federal income tax on
the disposition of such stock.

      Federal estate tax

         If you are an individual, common or preferred stock held by you at the
time of your death will be included in your gross estate for United States
federal estate tax purposes, unless an applicable estate tax treaty provides
otherwise.

      Information reporting and backup withholding

         KeySpan will be required to report annually to the IRS and to you the
amount of dividends paid to you and the tax withheld from dividend payments made
to you, regardless of whether withholding was required. KeySpan may make
available to the tax authorities in the country in which you reside under the
provisions of an applicable income tax treaty copies of the information returns
reporting the dividends and withholding.

         Backup withholding generally will apply to dividends paid to you unless
you satisfy the certification requirements of applicable United States Treasury
regulations.

         Payment of the proceeds of a sale of the common or preferred stock to
you within the United States or conducted through some United States-related
financial intermediaries will be subject to both backup withholding and
information reporting unless (1)(a) you certify under penalties of perjury that
you are a non-United States holder and (b) the payor does not have actual
knowledge that you are a United States person or (2) you otherwise establish an
exemption.

         Any amounts withheld under the backup withholding rules may be allowed
as a refund or credit against your United States federal income tax liability
provided the required information is provided to the IRS.

         Special rules may apply to some non-United States holders, such as
"controlled foreign corporations", "passive foreign investment companies",
"foreign personal holding companies", certain United States expatriates and
corporations that accumulate earnings to avoid United States federal income tax,
that are subject to special treatment under the Code. These entities should
consult their own tax advisors to determine the United States federal, state,
local, and other tax consequences that may be relevant to them.

Preferred stock, depositary shares, stock purchase contracts, stock purchase
units, warrants and warrant units

         If you are considering the purchase of preferred stock, depositary
shares, stock purchase contracts, stock purchase units, warrants or warrant
units, you should carefully examine the applicable prospectus supplement
regarding the special United States federal income tax consequences, if any, of
the ownership and disposition of the preferred stock, depositary shares, stock
purchase contracts, stock purchase units, warrants or warrant units, including
any tax considerations relating to the specific terms of the preferred stock,
depositary shares, stock purchase contracts, stock purchase units, warrants or
warrant units.








                              ERISA Considerations


         The following is a summary of certain considerations associated with
the purchase of the debt securities, preferred stock, depositary shares, common
stock, stock purchase units, stock purchase contracts, trust preferred
securities, warrants or warrants units by employee benefit plans that are
subject to Title I of the U.S. Employee Retirement Income Security Act of 1974,
as amended ("ERISA"), plans, individual retirement accounts and other
arrangements that are subject to Section 4975 of the Code or provisions under
any federal, state, local, non-U.S. or other laws or regulations that are
similar to such provisions of the Code or ERISA, and entities whose underlying
assets are considered to include "plan assets" of such plans, accounts and
arrangements (each, a "covered plan").

General fiduciary matters

         ERISA and the Code impose duties on fiduciaries of a covered plan
subject to Title I of ERISA or Section 4975 of the Code and prohibit
transactions involving the assets of a covered plan and its fiduciaries or other
interested parties. Under ERISA and the Code, any person who exercises any
discretionary authority or control over the administration of a covered plan or
the management or disposition of the assets of a covered plan, or who renders
investment advice for compensation to a covered plan, is generally considered a
fiduciary of the covered plan.

         In considering investing assets of any covered plan in the offered
securities, a fiduciary should determine whether the investment complies with
the documents and instruments governing the covered plan and the applicable
provisions of ERISA, the Code or any similar law relating to a fiduciary's
duties to the covered plan, including, the prudence, diversification, delegation
of control and prohibited transaction provisions of ERISA, the Code and any
other applicable similar laws.

         Any insurance company investing its general account assets in the
offered securities should consider whether the investment would be subject to
the requirements of ERISA in light of the U.S. Supreme Court's decision in John
Hancock Mutual Life Insurance Co. v. Harris Trust and Savings Bank and under any
subsequent legislation or other guidance that has or may become available
relating to that decision, including the enactment of Section 401(c) of ERISA by
the Small Business Job Protection Act of 1996 and its regulations.

Prohibited Transaction Issues

         Section 406 of ERISA and Section 4975 of the Code prohibit covered
plans subject to Title I of ERISA or Section 4975 of the Code from engaging in
specified transactions with "parties in interest," within the meaning of ERISA,
or "disqualified persons," within the meaning of Section 4975 of the Code,
unless an exemption is available. A party in interest or disqualified person who
engages in a non-exempt prohibited transaction may be subject to excise taxes
and other penalties and liabilities under ERISA and the Code. In addition, the
fiduciary of a covered plan that engages in such a non-exempt prohibited
transaction may be subject to penalties and liabilities under ERISA and the
Code.

         The acquisition and/or holding of the offered securities by a covered
plan with respect to which KeySpan, the trusts, an underwriter or an agent is
considered a party in interest or a disqualified person may result in a
prohibited transaction under Section 406 of ERISA and/or Section 4975 of the
Code, unless the investment is acquired and is held in accordance with an
applicable exemption. The U.S. Department of Labor has issued prohibited
transaction class exemptions, or "PTCEs," that may apply to the offered
securities. These class exemptions include, without limitation:

          -    PTCE 84-14  respecting  transactions  determined  by  independent
               qualified professional asset managers;

          -    PTCE 90-1 respecting insurance company pooled separate accounts;

          -    PTCE 91-38 respecting bank collective investment funds;

          -    PTCE 95-60  respecting life insurance  company general  accounts;
               and

          -    PTCE 96-23 respecting  transactions  determined by in-house asset
               managers,

although  there  can be no  assurance  that  all of the  conditions  of any such
exemptions will be satisfied.

Plan Asset Issues

         ERISA and the Code do not define "plan assets." However, the "Plan
Asset Regulations" under ERISA provide that when a covered plan subject to Title
I of ERISA or Section 4975 of the Code acquires an equity interest in an entity
that is neither a "publicly-offered security" nor a security issued by an
investment company registered under the Investment Company Act, the covered
plan's assets include both the equity interest and an undivided interest in each
of the underlying assets of the entity unless that equity participation by
"benefit plan investors" is not significant or the entity is an "operating
company," in each case as defined in the plan asset regulations. The plan asset
regulations define an "equity interest" as any interest, other than an
instrument that is treated as indebtedness under applicable local law and which
has no substantial equity features. Equity participation in an entity by benefit
plan investors will not be significant if they hold, in the aggregate, less than
25% of the value of any class of such entity's equity, excluding equity
interests held by persons (other than benefit plan investors) with discretionary
authority or control over the assets of the entity or who provide investment
advice for a fee with respect to such assets, and any affiliates thereof. For
purposes of this 25% test, "benefit plan investors" include all employee benefit
plans, including "Keogh" plans, individual retirement accounts and pension plans
maintained by foreign corporations, as well as any entity whose underlying
assets are deemed to include "plan assets" under the plan asset regulations. The
Department of Labor has stated that in determining whether equity participation
in an entity by benefit plan investors is "significant," only the proportion of
an insurance company general account's equity investment in the entity that
represents plan assets should be taken into account and, therefore, the
proportion of that investment that represents plan assets would equal the
proportion of the insurance company general account as a whole that constitutes
plan assets.

         For purposes of the plan asset regulations, a "publicly offered
security" is a security that is:

          -    "freely transferable,"

          -    "widely held," and

          -    (1)  sold as part of an  offering  of  securities  to the  public
               pursuant  to  an  effective   registration  statement  under  the
               Securities Act of 1933 and such security is registered  under the
               Securities  Exchange Act of 1934 within 120 days after the end of
               the fiscal year of the issuer  during  which the offering of such
               securities to the public has occurred,  or (2)  registered  under
               Section 12 of the Exchange Act.

         KeySpan expects to qualify as an operating company within the meaning
of the plan asset regulations. KeySpan does not anticipate that the trust
preferred securities will constitute "publicly offered securities" for purposes
of the plan asset regulations, that any of the trusts will be an investment
company registered under the Investment Company Act or that any of the trusts
will qualify as an operating company within the meaning of the plan asset
regulations. In addition, if benefit plan investors invested in the trust
preferred securities, the trusts would not be in a position to monitor whether
those investments would be "significant" for purposes of the plan asset
regulations.

Plan asset consequences

         If the assets of KeySpan or the trusts were deemed to be "plan assets"
under ERISA, this would result, among other things, in:

          -    the   application   of   the   prudence   and   other   fiduciary
               responsibility  standards of ERISA to investments made by KeySpan
               and the trusts; and

          -    the  possibility  that certain  transactions in which KeySpan and
               the trusts  might  seek to engage  could  constitute  "prohibited
               transactions" under ERISA and the Code.

         Because of the foregoing, the offered securities other than trust
preferred securities (the "KeySpan Securities") should not be purchased or held
by any person investing "plan assets" of any covered plan, if the purchase and
holding will constitute a non-exempt prohibited transaction under ERISA and the
Code or will violate any applicable similar laws.

         Because of the foregoing, the trust preferred securities should not be
purchased or held by any person investing "plan assets" of any Plan (as defined
below), except that an insurance company general account may purchase or hold
the trust preferred securities if:

          -    such  purchase  and  holding  will not  constitute  a  non-exempt
               prohibited  transaction  under  ERISA  and the  Code and will not
               violate any applicable similar laws; and

          -    less than 25% of the  assets of such  insurance  company  general
               account will constitute "plan assets" of any Plan.

Representation

         Accordingly, by accepting the offered securities other than trust
preferred securities, each purchaser and subsequent transferee of those
securities will be deemed to have represented and warranted that either:

          -    no assets used to acquire those securities  constitutes assets of
               any covered plan; or

          -    the purchase and holding of those securities by such purchaser or
               transferee   will  not   constitute   a   non-exempt   prohibited
               transaction  under  Section  406 of ERISA or Section  4975 of the
               Code and will not violate any applicable similar laws.

         By accepting the trust preferred securities, each purchaser and
subsequent transferee of the trust preferred securities will be deemed to have
represented and warranted either that:

          -    for the entire  period  during which it holds its interest in the
               trust preferred securities, no portion of such assets constitutes
               assets of any  "employee  benefit  plan"  within  the  meaning of
               Section  3(3) of  ERISA,  whether  or not  subject  to Title I of
               ERISA, including any U.S. governmental or non-U.S.  pension plan,
               or any "plan" subject to Section 4975 of the Code (each a "Plan")
               or

          -    (x) the assets  used to acquire  the trust  preferred  securities
                   constitute assets of an insurance company general account,

               (y)  for  the  entire  period  during  which  such  purchaser  or
                    transferee   holds  its  interest  in  the  trust  preferred
                    securities,  less than 25% of the  assets of such  insurance
                    company general account will constitute "plan assets" of any
                    Plan, and

               (z)  the   acquisition   and  holding  of  the  trust   preferred
                    securities  will satisfy the  requirements of the Department
                    of Labor's Prohibited  Transaction Class Exemption 95-60 and
                    will not  constitute  a  non-exempt  prohibited  transaction
                    under Section 406 of ERISA or Section 4975 of the Code.

         Due to the complexity of these rules and the penalties that may be
imposed upon persons involved in non-exempt prohibited transactions, it is
particularly important that fiduciaries, or other persons purchasing on behalf
of, or with the assets of, any employee benefit plan, consult with their counsel
to determine whether such employee benefit plan is subject to Title I of ERISA,
Section 4975 of the Code or any similar laws.









                              Plan of Distribution


         KeySpan may sell the offered securities as follows:

               -    through underwriters or dealers; or

               -    through agents; or

               -    directly to purchasers.

         The prospectus supplement or term sheet for each offering of securities
will describe that offering, including:

               -    the name or names of any underwriters, dealers or agents;

               -    the  purchase  price and the  proceeds to KeySpan  from that
                    sale;

               -    any  underwriting  discounts  and other  items  constituting
                    underwriters' compensation;

               -    any  initial  public  offering  price and any  discounts  or
                    concessions allowed or reallowed or paid to dealers; and

               -    any  securities  exchanges on which the debt  securities  of
                    that series may be listed.

Underwriters

         Unless otherwise set forth in the prospectus supplement or term sheet,
the obligations of the underwriters to purchase offered securities will be
subject to certain conditions. The underwriters will be obligated to purchase
all the offered securities if any are purchased.

         The offered securities will be acquired by the underwriters for their
own account and may be resold by them from time to time in one or more
transactions, including negotiated transactions, at a fixed public offering
price or at varying prices determined at the time of sale. Underwriters may be
deemed to have received compensation from KeySpan in the form of underwriting
discounts or commissions and may also receive commissions from the purchasers of
offered securities for whom they may act as agent. Underwriters may also sell
offered securities to or through dealers. These dealers may receive compensation
in the form of discounts, concessions or commissions from the underwriters
and/or commissions from the purchasers for whom they may act as agent. Any
initial public offering price and any discounts or concessions allowed or
reallowed or paid to dealers may be changed from time to time.

         KeySpan may authorize underwriters to solicit offers by certain types
of institutions to purchase offered securities from it at the public offering
price stated in the prospectus supplement or term sheet required by delayed
delivery contracts providing for payment and delivery on a specified date in the
future. If KeySpan sells debt securities under these delayed delivery contracts,
the prospectus supplement or term sheet will state that as well as the
conditions to which these delayed delivery contracts will be subject and the
commissions payable for that solicitation.

Agents

         KeySpan may also sell offered securities through agents designated by
it from time to time. KeySpan will name any agents involved in the offer or sale
of the offered securities and will list commissions payable by it to these
agents in the prospectus supplement or term sheet. These agents will be acting
on a best efforts basis to solicit purchases for the period of their
appointment, unless KeySpan states otherwise in the prospectus supplement or
term sheet.

Direct sales

         KeySpan may sell offered securities directly to purchasers. In this
case, KeySpan will not engage underwriters or agents in the offer and sale of
offered securities.

Remarketing transactions

         KeySpan may also sell offered securities that it has purchased,
redeemed or repaid or which are being remarketed on behalf of holders through
one or more remarketing firms acting as principals for their own accounts or as
KeySpan's agents. The applicable prospectus supplement or term sheet will
identify any remarketing firms and describe the terms of KeySpan's agreement
with them and their compensation. Remarketing firms may be deemed to be
underwriters of the offered securities under the Securities Act.

Indemnification

         KeySpan may indemnify underwriters, dealers or agents who participate
in the distribution of offered securities against certain liabilities, including
liabilities under the Securities Act, and agree to contribute to payments which
these underwriters, dealers or agents may be required to make.

No assurance of liquidity

         Some of the offered securities will be new issues of securities with no
established trading market. Any underwriters that purchase offered securities
from KeySpan may make a market in these debt securities. The underwriters will
not be obligated, however, to make a market in the offered securities and may
discontinue market-making at any time without notice to holders of those
securities. KeySpan cannot assure you that there will be liquidity in the
trading market for any offered securities of any series.

                                 Legal Opinions


         The validity of the securities offered by KeySpan in this prospectus
will be passed upon for it by Simpson Thacher & Bartlett, New York, New York and
the validity of the trust preferred securities offered by the trusts will be
passed upon by Richards, Layton & Finger, P.A. Certain legal matters will be
passed upon for any agents or underwriters by Simpson Thacher & Bartlett or
other counsel identified in the prospectus supplement or term sheet.

                                     Experts


         Arthur Andersen LLP, independent accountants, audited the financial
statements for the nine months ended December 31, 1998 and the twelve months
ended December 31, 1999 and the twelve months ended December 31, 2000, and
related schedules incorporated by reference in this prospectus. Arthur Andersen
LLP, also audited the financial statements for Eastern Enterprises for the
twelve months ended December 31, 1998 and December 31, 1999, and related
schedules incorporated by reference in this prospectus. These financial
statements and schedules are incorporated by reference herein in reliance upon
the authority of Arthur Andersen LLP, as experts in accounting and auditing in
giving the reports.

                       Where You Can Find More Information


         KeySpan files annual, quarterly and special reports, proxy statements
and other information with the SEC. You may read and copy any of these documents
at the SEC's public reference rooms in Washington, D.C., New York, New York and
Chicago, Illinois. Please call the SEC at 1-800-SEC-0330 for further information
on the public reference rooms. KeySpan's SEC filings are also available to the
public on the SEC's web site at http://www.sec.gov.

         KeySpan and the trusts filed a registration statement on Form S-3 with
the SEC covering the offered securities. For further information on KeySpan and
the offered securities, you should refer to the registration statement and its
exhibits. This prospectus summarizes material provisions of the offered
securities. Because the prospectus may not contain all the information that you
may find important, you should review the full text of these documents. KeySpan
and the trusts have included copies of these documents in an exhibit to its
registration statement of which this prospectus is a part.

         The SEC allows KeySpan to "incorporate by reference" the information
that it files with the SEC, which means that KeySpan can disclose important
information to you by referring you to those documents. The information
incorporated by reference is considered to be part of this prospectus, and later
information that KeySpan files with the SEC will automatically update and
supersede this information. KeySpan incorporates by reference the documents
listed below and any future filings made with the SEC under Sections 13(a),
13(c), 14, or 15(d) of the Securities Exchange Act of 1934 until all of the
securities are sold.

               -    KeySpan's  Annual  Report on Form 10-K for the  fiscal  year
                    ended December 31, 2000;

               -    Quarterly  Reports on Form 10-Q for the quarter  ended March
                    31, June 30 and September 30, 2001; and

               -    KeySpan's Current Reports on Form 8-K filed October 6, 2000;
                    January  25,  May 24,  July  17,  July  26,  October  24 and
                    December 6, 2001; and January 24, 2002.

         You may request a copy of these filings, or any of KeySpan's or the
trusts' SEC filings, at no cost, over the Internet at its web site at
http://www.keyspanenergy.com or by writing or telephoning KeySpan at the
following address:

                               Investor Relations
                               KeySpan Corporation
                              One MetroTech Center
                            Brooklyn, New York, 11201
                                 (718) 403-3385










                                     PART II

                     INFORMATION NOT REQUIRED IN PROSPECTUS

Item 14.  Other Expenses of Issuance and Distribution.


         The expenses in connection with the issuance and distribution of the
securities being registered, other than the underwriting discounts and
commissions, are as follows:
                                                                                            
Securities and Exchange Commission Registration Fee.............................................$110,400
New York Stock Exchange Listing Fee.............................................................$100,000
Legal Fees and Expenses.........................................................................$250,000
Accountants Fees and Expenses....................................................................$50,000
Blue sky fees and expenses.......................................................................$10,000
Trustee Fees and Expenses........................................................................$20,000
Rating Agency Fees..............................................................................$100,000
Printing and Delivery Expenses...................................................................$75,000
Miscellaneous Expenses............................................................................$4,600
                                                                                                   -----
      Total*....................................................................................$720,000
                                                                                                 =======


- --------------
*  All of the above expenses are estimated except for the SEC filing fee.

Item 15.  Indemnification of Directors and Officers.

         The New York Business Corporation Law ("BCL"), Article 7, Sections
721-726 provide for the indemnification and advancement of expenses to officers
and directors. Section 721 provides that indemnification and advancement
pursuant to the BCL are not exclusive of any other rights an officer or director
may be entitled to, provided that no indemnification may be made to or on behalf
of any director or officer if a judgment or other final adjudication adverse to
the director or officer establishes that his acts were committed in bad faith or
were the result of active and deliberate dishonesty and were material to the
cause of action so adjudicated, or that the director personally gained a
financial profit or other advantage to which he or she was not legally entitled.

         Section 722 of the BCL provides that a corporation may indemnify an
officer or director, in the case of third party actions, against judgments,
fines, amounts paid in settlement and reasonable expenses and, in the case of
derivative actions, against amounts paid in settlement and reasonable expenses,
provided that the director or officer acted in good faith, for a purpose which
he or she reasonably believed to be in the best interests of the corporation
and, in the case of criminal actions, had no reasonable cause to believe his
conduct was unlawful. In addition, statutory indemnification may not be provided
in derivative actions (i) which are settled or otherwise disposed of or (ii) in
which the director or officer is adjudged liable to the corporation, unless and
only to the extent a court determines that the person is fairly and reasonably
entitled to indemnity.

         Section 723 of the BCL provides that statutory indemnification is
mandatory where the director or officer has been successful, on the merits or
otherwise, in the defense of a civil or criminal action or proceeding. Section
723 also provides that expenses of defending a civil or criminal action or
proceeding may be advanced by the corporation upon receipt of an undertaking to
repay them if and to the extent the recipient is ultimately found not to be
entitled to indemnification. Section 725 provides for repayment of such expenses
when the recipient is ultimately found not to be entitled to indemnification.
Section 726 provides that a corporation may obtain indemnification insurance
indemnifying itself and its directors and officers. KeySpan Corporation has in
effect insurance policies providing both directors and officers liability
coverage and corporate reimbursement coverage.

         Section 402(b) of the BCL provides that a corporation may include in
its certificate of incorporation a provision limiting or eliminating, with
certain exceptions, the personal liability of directors to a corporation or its
shareholders for damages for any breach of duty in such capacity. The
certificate of incorporation of KeySpan Corporation contains provisions
eliminating the personal liability of directors to the extent permitted by New
York law.

         The KeySpan Corporation's certificate of incorporation provides
generally that it shall, except to the extent expressly prohibited by the BCL,
indemnify each of its officers and directors made or threatened to be made a
party to any action, suit or proceeding, or appeal thereof, whether civil or
criminal by reason of the fact that such person is or was an officer or director
against all expense, liability and loss (including, but not limited to all
attorneys' fees, judgments, fines, pension plan taxes or penalties and amounts
paid or to be paid in settlement) reasonably incurred or suffered by such person
in connection therewith. The certificate of incorporation further provides for
advancement and reimbursement of such expenses incurred by an officer or
director in defending any action or proceeding in advance of the final
disposition thereof upon receipt of an undertaking by such person to repay such
amount if, and to the extent that, such person is ultimately found not to be
entitled to indemnification.

Item 16.  List of Exhibits.

         See Exhibit Index

Item 17.  Undertakings.

      (a)The undersigned registrant hereby undertakes:

            (1) To file, during any period in which offers or sales are being
      made, a post-effective amendment to this registration statement:

               (i)  To include any  prospectus  required by Section  10(a)(3) of
                    the Securities Act of 1933;

               (ii) To reflect  in the  prospectus  any facts or events  arising
                    after the effective date of the  registration  statement (or
                    the most recent  post-effective  amendment  thereof)  which,
                    individually  or in the  aggregate,  represent a fundamental
                    change  in the  information  set  forth in the  registration
                    statement.  Notwithstanding  the foregoing,  any increase or
                    decrease  in  volume  of  securities  offered  (if the total
                    dollar  value of  securities  offered  would not exceed that
                    which was registered) and any deviation from the low or high
                    end of the estimated maximum offering range may be reflected
                    in the form of prospectus filed with the Commission pursuant
                    to Rule 424(b) if, in the  aggregate,  the changes in volume
                    and price represent no more than a 20% change in the maximum
                    aggregate  offering price set forth in the  "Calculation  of
                    Registration  Fee"  table  in  the  effective   registration
                    statement;

               (iii)To include  any  material  information  with  respect to the
                    plan  of  distribution  not  previously   disclosed  in  the
                    Registration  Statement  or  any  material  change  to  such
                    information in the Registration Statement;

provided, however, that paragraphs (a)(1)(i) and (a)(1)(ii) do not apply if the
Registration Statement is on Form S-3, Form S-8, or Form F-3 and the information
required to be included in a post-effective amendment by those paragraphs is
contained in periodic reports filed with or furnished to the Securities and
Exchange Commission by the registrant pursuant to Section 13 or Section 15(d) of
the Securities Exchange Act of 1934 that are incorporated by reference in the
Registration Statement.

            (2) That, for the purpose of determining any liability under the
      Securities Act of 1933, each such post-effective amendment shall be deemed
      to be a new registration statement relating to the securities offered
      therein, and the offering of such securities at that time shall be deemed
      to be the initial bona fide offering thereof.

            (3) To remove from registration by means of a post-effective
      amendment any of the securities being registered which remain unsold at
      the termination of the offering.

         (b) The undersigned registrant hereby undertakes that, for purposes of
      determining any liability under the Securities Act of 1933, each filing of
      the registrant's annual report pursuant to Section 13(a) or Section 15(d)
      of the Securities Exchange Act of 1934 (and, where applicable, each filing
      of an employee benefit plan's annual report pursuant to Section 15(d) of
      the Securities Exchange Act of 1934) that is incorporated by reference in
      the registration statement shall be deemed to be a new registration
      statement relating to the securities offered therein, and the offering of
      such securities at that time shall be deemed to be the initial bona fide
      offering thereof.

         (c) Insofar as indemnification for liabilities arising under the
      Securities Act of 1933 may be permitted to directors, officers and
      controlling persons of such registrant pursuant to the provisions referred
      to in Item 15 of this registration statement, or otherwise, the registrant
      has been advised that in the opinion of the Securities and Exchange
      Commission such indemnification is against public policy as expressed in
      such Act and is, therefore, unenforceable. In the event that a claim for
      indemnification against such liabilities (other than the payment by such
      registrants of expenses incurred or paid by a director, officer or
      controlling person of such registrants in the successful defense of any
      action, suit or proceeding) is asserted by such director, officer or
      controlling person in connection with the securities being registered, the
      registrant will, unless in the opinion of its counsel the matter has been
      settled by controlling precedent, submit to a court of appropriate
      jurisdiction the question whether such indemnification by it is against
      public policy as expressed in the Securities Act of 1933 and will be
      governed by the final adjudication of such issue.







                                   SIGNATURES

         Pursuant to the requirements of the Securities Act of 1933, KeySpan
Corporation certifies that it has reasonable grounds to believe that it meets
all of the requirements for filing on Form S-3 and has duly caused this
registration statement to be signed on its behalf by the undersigned, thereunto
duly authorized, in the City of Brooklyn, State of New York, on this 6th day of
February, 2002.

                                          KEYSPAN CORPORATION
                                          Issuer of Securities
                                          (Registrant)

                                          By: /s/ Gerald Luterman
                                              -------------------
                                          Gerald Luterman
                                          Chief Financial Officer and Executive
                                          Vice-President
                                          (Principal Financial Officer)


         Pursuant to the requirements of the Securities Act of 1933, this
registration statement has been signed below by the following persons in the
capacities and on the dates indicated.



                                                             Date:

                            *                                February 6, 2002
- -----------------------------------------------------------
Robert B. Catell
Chief Executive Officer and Director
(Principal Executive Officer)



/s/ Gerald Luterman                                          February 6, 2002
- -----------------------------------------------------------
Gerald Luterman
Chief Financial Officer and Executive Vice-President
(Principal Financial Officer)



/s/ Ronald Jendras                                           February 6, 2002
- -----------------------------------------------------------
Ronald Jendras
Vice President, Controller and Chief Accounting Officer
(Principal Accounting Officer)



                            *                                February 6, 2002
- -----------------------------------------------------------
Lilyan H. Affinito
Director



                            *                                February 6, 2002
- -----------------------------------------------------------
Andrea S. Christensen
Director



                            *                                February 6, 2002
- -----------------------------------------------------------
Howard R. Curd
Director



                            *                                February 6, 2002
- -----------------------------------------------------------
Donald H. Elliott
Director



                            *                                February 6, 2002
- -----------------------------------------------------------
Alan H. Fishman
Director



                            *                                February 6, 2002
- -----------------------------------------------------------
Vicki L. Fuller
Director



                            *                                February 6, 2002
- -----------------------------------------------------------
J. Atwood Ives
Director



                            *                                February 6, 2002
- -----------------------------------------------------------
James R. Jones
Director



                            *                                February 6, 2002
- -----------------------------------------------------------
James L. Larocca
Director



                            *                                February 6, 2002
- -----------------------------------------------------------
Craig G. Matthews
Director



                            *                                February 6, 2002
- -----------------------------------------------------------
Stephen W. McKessy
Director



                            *                                February 6, 2002
- -----------------------------------------------------------
Edward D. Miller
Director



                            *                                February 6, 2002
- -----------------------------------------------------------
James Q. Riordan
Director



*By: /s/ Ronald Jendras                                      February 6, 2002
     -----------------------------------------
         Ronald Jendras, as Attorney-in-Fact








         Pursuant to the requirements of the Securities Act of 1933, KeySpan
Trust I, KeySpan Trust II and KeySpan Trust III each certifies that it has
reasonable grounds to believe that it meets all of the requirements for filing
on Form S-3 and has duly caused this registration statement to be signed on its
behalf by the undersigned, thereunto duly authorized, in the City of Brooklyn,
State of New York, on the 6th of February, 2002.



                                                     KEYSPAN TRUST I



                                                     /s/ Ronald S. Jendras
                                                     ---------------------------
                                                     Ronald S. Jendras
                                                     Trustee



                                                     /s/ Richard A. Rapp
                                                     ---------------------------
                                                     Richard A. Rapp
                                                     Trustee



                                                     /s/ Michael J. Taunton
                                                     ---------------------------
                                                     Michael J. Taunton
                                                     Trustee




                                                     KEYSPAN TRUST II



                                                     /s/ Ronald S. Jendras
                                                     ---------------------------
                                                     Ronald S. Jendras
                                                     Trustee



                                                     /s/ Richard A. Rapp
                                                     ---------------------------
                                                     Richard A. Rapp
                                                     Trustee



                                                     /s/ Michael J. Taunton
                                                     ---------------------------
                                                     Michael J. Taunton
                                                     Trustee




                                                     KEYSPAN TRUST III



                                                     /s/ Ronald S. Jendras
                                                     ---------------------------
                                                     Ronald S. Jendras
                                                     Trustee



                                                     /s/ Richard A. Rapp
                                                     ---------------------------
                                                     Richard A. Rapp
                                                     Trustee



                                                     /s/ Michael J. Taunton
                                                     ---------------------------
                                                     Michael J. Taunton
                                                     Trustee









                                  EXHIBIT INDEX

     1.1** Form of underwriting agreement for debt securities

     1.2* Form of underwriting agreement for preferred stock

     1.3* Form of underwriting agreement for depositary shares

     1.4* Form of underwriting agreement for trust preferred securities

     1.5* Form of underwriting agreement for common stock

     1.6* Form of underwriting agreement for stock purchase contracts

     1.7* Form of underwriting agreement for stock purchase units

     4.1  Certificate of  Incorporation of KeySpan  Corporation  effective April
          16, 1998,  Amendment to the  Certificate of  Incorporation  of KeySpan
          Corporation  effective May 26, 1998,  Amendment to the  Certificate of
          Incorporation of KeySpan Corporation effective June 1, 1998, Amendment
          to the Certificate of Incorporation of KeySpan  Corporation  effective
          April 7, 1999 and Amendment to the  Certificate  of  Incorporation  of
          KeySpan  Corporation  effective  May 20, 1999 (filed as Exhibit 3.1 to
          KeySpan  Corporation's  10-Q for the  quarterly  period ended June 30,
          1999 and incorporated herein by reference)

     4.2  ByLaws of KeySpan  Corporation  in effect on September  10,  1998,  as
          amended  (filed as Exhibit  3.1 to KeySpan  Corporation's  Form 8-K/A,
          Amendment  No. 2, on  September  29, 1998 and  incorporated  herein by
          reference)

     4.3** Form of Common Stock Certificate

     4.4  Indenture,  dated as of November 1, 2000, between KeySpan  Corporation
          and JPMorgan Chase Bank  (successor to The Chase  Manhattan  Bank), as
          trustee,  with respect to the senior debt securities (filed as Exhibit
          4.4 to KeySpan  Corporation's  registration  statement  on Form S-3/A,
          Amendment No.1, on May 17, 2001 and incorporated herein by reference).
          The forms of senior debt  securities  with respect to each  particular
          series of senior debt securities registered hereunder will be filed as
          an exhibit to a Current  Report on Form 8-K and shall be deemed to the
          incorporated herein by reference

     4.5**Form  of  Subordinated   Indenture  between  KeySpan  Corporation  and
          JPMorgan Chase Bank, as trustee, with respect to the subordinated debt
          securities.  The forms of subordinated debt securities with respect to
          each  particular  series of subordinated  debt  securities  registered
          hereunder  will be filed as an exhibit to a Current Report on Form 8-K
          and shall be deemed to be incorporated herein by reference.

     4.6**Form of First Supplemental Indenture,  between the KeySpan Corporation
          and JPMorgan  Chase Bank, as trustee,  with respect to the senior debt
          securities

     4.7**Form of Supplemental  Indenture  relating to  subordinated  debentures
          for trust  preferred  securities  issuance 4.8 Certificate of Trust of
          KeySpan  Trust  I  (filed  as  Exhibit  4.7 to  KeySpan  Corporation's
          registration  statement on Form S-3/A, Amendment No.1, on May 17, 2001
          and incorporated herein by reference)

     4.9  Certificate  of Trust of  KeySpan  Trust II (filed as  Exhibit  4.8 to
          KeySpan Corporation's  registration statement on Form S-3/A, Amendment
          No.1, on May 17, 2001 and incorporated herein by reference)

     4.10 Certificate  of Trust of KeySpan  Trust III  (filed as Exhibit  4.9 to
          KeySpan Corporation's  registration statement on Form S-3/A, Amendment
          No.1, on May 17, 2001 and incorporated herein by reference)

     4.11 Declaration  of Trust of  KeySpan  Trust I (filed as  Exhibit  4.10 to
          KeySpan Corporation's  registration statement on Form S-3/A, Amendment
          No.1, on May 17, 2001 and incorporated herein by reference)

     4.12 Declaration  of Trust of KeySpan  Trust II (filed as  Exhibit  4.11 to
          KeySpan Corporation's  registration statement on Form S-3/A, Amendment
          No.1, on May 17, 2001 and incorporated herein by reference)

     4.13 Declaration  of Trust of KeySpan  Trust III (filed as Exhibit  4.12 to
          KeySpan Corporation's  registration statement on Form S-3/A, Amendment
          No.1, on May 17, 2001 and incorporated herein by reference)

     4.14** Form of Amended  and  Restated  Declaration  of Trust for each trust
          (including the forms of preferred  security and common  security to be
          issued thereunder)

     4.15** Form of Guarantee  with respect to the preferred  securities of each
          trust

     4.16 Rights Agreement,  dated March 30, 1999, by and between the Registrant
          and The Bank of New York,  as Rights  Agent (filed as Exhibit 4 to the
          Registrant's  Current  Report on Form 8-K filed on March 30,  1999 and
          incorporated  herein by reference).  The Rights Agreement includes the
          Certificate of Amendment to the Certificate of  Incorporation  for the
          Series D  Preferred  Stock as  Exhibit A  thereto,  the Form of Rights
          Certificate as Exhibit B thereto and the Summary of Rights to Purchase
          Series D Preferred Stock as Exhibit C thereto.

     4.17** Form of Certificate of Amendment with respect to the preferred stock

     4.18** Form of deposit  agreement  with  respect to the  depository  shares
          (including form of depository receipts to be issued thereunder)

     4.19** Form of Purchase Contract Agreement

     4.20** Form of Debt Warrant Agreement

     4.21** Form of Stock Warrant Agreement

     4.22** Form of Unit Agreement

     4.23** Form of subordinated debt security to be issued to each trust

     4.24** Form of senior debt security to be issued

     5.1**Opinion and consent of Simpson  Thacher & Bartlett as to the  validity
          of  the  debt   securities,   preferred  stock,   depositary   shares,
          guarantees, common stock, rights to purchase Series D preferred stock,
          stock purchase units, stock purchase  contracts,  warrants and warrant
          units of KeySpan Corporation being registered

     5.2**Opinion  and  consent of  Richards,  Layton & Finger,  P.A.  as to the
          validity of the trust preferred securities being registered

     8.1**Opinion and consent of Simpson  Thacher & Bartlett  regarding  certain
          tax matters

     12.1**  Computation  in support of ratio of earnings  to fixed  charges and
          ratio of combined fixed charges and preferred dividends

     23.1 Consent of Simpson Thacher & Bartlett (Included in Exhibit 5.1 above)

     23.2 Consent of Richards,  Layton & Finger,  P.A.  (Included in Exhibit 5.2
          above)

     23.3** Consent of Arthur Andersen LLP

     23.4** Consent of Arthur Andersen LLP

     23.5 Consent of Simpson Thacher & Bartlett (Included in Exhibit 8.1 above)

     24.1** Powers of attorney

     25.1** Form T-1 statement of eligibility and qualification  under the Trust
          Indenture Act of 1939 (a "Form T-1") of JPMorgan Chase Bank ("Chase"),
          as  trustee  under the  indenture  with  respect  to the  senior  debt
          securities

     25.2** Form T-1 of Chase as trustee under the indenture with respect to the
          subordinated debt securities

     25.3** Form T-1 of Chase  as  trustee  under  the  declaration  of trust of
          KeySpan Trust I

     25.4** Form T-1 of Chase  as  trustee  under  the  declaration  of trust of
          KeySpan Trust II

     25.5** Form T-1 of Chase  as  trustee  under  the  declaration  of trust of
          KeySpan Trust III

     25.6** Form T-1 of Chase as trustee  under the guarantee for the benefit of
          holders of trust preferred securities of KeySpan Trust I

     25.7** Form T-1 of Chase as trustee  under the guarantee for the benefit of
          holders of trust preferred securities of KeySpan Trust II

     25.8** Form T-1 of Chase as trustee  under the guarantee for the benefit of
          holders of trust preferred securities of KeySpan Trust III


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*     To be filed as an Exhibit to a Current Report on Form 8-K

**    Filed herewith.