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                                                                     EXHIBIT 4.3
                            THE ALLSTATE CORPORATION

                        SECOND SUPPLEMENTAL INDENTURE TO
                       INDENTURE DATED DECEMBER 16, 1997
                            (SENIOR DEBT SECURITIES)

                                  $500,000,000

                    6.75% Senior Debentures due May 15, 2018
                    6.90% Senior Debentures due May 15, 2038

     SECOND SUPPLEMENTAL INDENTURE, dated as of May 20, 1998, between THE
ALLSTATE CORPORATION, a Delaware corporation (the "Company"), and STATE STREET
BANK AND TRUST COMPANY, a Massachusetts trust company, as Trustee (the
"Trustee").

                                    RECITALS

     The Company has heretofore executed and delivered to the Trustee an
Indenture for  Senior Debt Securities, dated as of December 16, 1997 (the
"Indenture"), providing for the issuance from time to time of series of the
Company's Securities.

     On December 16, 1997, the Company executed and delivered to the Trustee a
First Supplemental Indenture to the Indenture (the "First Supplemental
Indenture"), providing for the issuance of $250,000,000 in principal amount of
7 1/8 % Senior Quarterly Interest Bonds due 2097 (the "2097 Senior Bonds").
The Company issued the 2097 Senior Bonds on December 19, 1997.

     Section 301 of the Indenture provides for various matters with respect to
any series of Securities issued under the Indenture to be established in an
indenture supplemental to the Indenture.

     Section 901(7) of the Indenture provides for the Company and the Trustee
to enter into an indenture supplemental to the Indenture to establish the form
or terms of Securities of any series as provided by Sections 201 and 301 of the
Indenture.

     NOW, THEREFORE, THIS SECOND SUPPLEMENTAL INDENTURE WITNESSETH:

     For and in consideration of the premises and the issuance of the series of
Securities provided for herein, it is mutually agreed, for the equal and
proportionate benefit of all Holders of the Securities of such series, as
follows:




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                                   ARTICLE I
                       Relation to Indenture; Definitions

     Section 1.1. Relation to Indenture.  This Second Supplemental Indenture
constitutes an integral part of the Indenture.
     Section 1.2. Definitions.  For all purposes of this Second Supplemental
Indenture:

     (a) Capitalized terms used herein without definition shall have the
meanings specified in the Indenture;

     (b) All references herein to Articles and Sections, unless otherwise
specified, refer to the corresponding Articles and Sections of this Second
Supplemental Indenture; and

     (c) The terms "herein," "hereof," "hereunder" and other words of similar
import refer to this Second Supplemental Indenture.

                                   ARTICLE II

                            The Series of Securities

     Section 2.1. Title of the Securities.  There shall be a series of
Securities designated the "6.75% Senior Debentures due May 15, 2018" (the "2018
Debentures") and a series of Securities designated the "6.90% Senior Debentures
due May 15, 2038" (the "2038 Debentures," and collectively with the 2018
Debentures, the "Debentures").

     Section 2.2. Limitation on Aggregate Principal Amount; Date of
Debentures.  The aggregate principal amount of each series of Debentures which
may be authenticated and delivered under this Supplemental Indenture shall be
limited to $250,000,000 (except for  Debentures which may be authenticated and
delivered upon transfer of, or in exchange for, or in lieu of Debentures
pursuant to the Indenture).

     Section 2.3. Principal Payment Date.   The principal amount of each series
of the Debentures (together with any accrued and unpaid interest) shall be
payable in a single installment on the Stated Maturity of the principal amount
of such series of Debentures, which, in the case of the 2018 Debentures, shall 
be May 15, 2018, and in the case of the 2038 Debentures,
shall be May 15, 2038.

     Section 2.4. Interest and Interest Rates.  The rate of interest on each
2018 Debenture shall be 6.75% per annum and the rate of interest on each 2038
Debenture shall be 6.90%


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per annum, in each case accruing from May 26, 1998, or from the most recent
interest payment date (each such date, an "Interest Payment Date") to which
interest has been paid or duly provided for, payable semiannually in arrears on
May 15 and November 15 of each year commencing November 15, 1998 until the
principal thereof shall have become due and payable, and until the principal
hereof is paid or duly provided for or made available for payment.  The amount
of interest payable on any Interest Payment Date shall be computed on the basis
of a 360-day year of twelve 30-day months.  The amount of interest payable for
any partial period shall be computed on the basis of the actual number of days
elapsed in a 360-day year of twelve 30-day months.  In the event that any date
on which interest is payable on any Debenture is not a Business Day, then
payment of interest payable on such date will be made on the next succeeding
day that is a Business Day (and without any interest or other payment in
respect of any such delay).  A "Business Day" shall mean any day, other than a
Saturday or Sunday, on which banks in the City of New York are not required by
law to close.  The interest installment so payable in respect of any Debenture,
and punctually paid or duly provided for, on any Interest Payment Date will, as
provided in the Indenture, be paid to the person in whose name such Debenture
(or one or more Predecessor Securities) is registered at the close of business
on the preceding April 30, if the Interest Payment Date is May 15, or October
31, if the Interest Payment Date is November 15 (a "Regular Record Date").  Any
such interest installment not punctually paid or duly provided for in respect
of any Debenture shall forthwith cease to be payable to the registered Holder
on such Regular Record Date and may either be paid to the Person in whose name
such Debenture (or one or more Predecessor Securities) is registered at the
close of business on a Special Record Date to be fixed by the Trustee for the
payment of such Defaulted Interest, notice whereof shall be given to the
Holders of Debentures not less than 10 days prior to such Special Record Date,
or be paid at any time in any other lawful manner not inconsistent with the
requirements of any securities exchange on which the Debentures may be listed,
and upon such notice as may be required by such exchange, all as more fully
provided in the Indenture.

     Section 2.5. Place of Payment.  The Place of Payment where the Debentures
may be presented or surrendered for payment, where the Debentures may be
surrendered for registration of transfer or exchange and where notices and 
demand to or upon the Company in respect of the Debentures and the Indenture 
may be served shall be the Corporate Trust Office of the Trustee.

     Section 2.6. Denomination.  The Debentures shall be issuable  in
book-entry form only and in denominations of $1,000 and integral multiples
thereof.

     Section 2.7. Currency.  Principal and interest on the Debentures shall be
payable in such coin or currency of the United States of America that at the
time of payment is legal tender for payment of public and private debts.

     Section 2.8. Form of Debentures.  The Debentures shall be substantially in
the form attached as Exhibit A hereto.


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     Section 2.9. Securities Registrar and Paying Agent.  The Trustee shall
serve initially as Securities Registrar and Paying Agent.

     Section 2.10. Sinking Fund Obligations.  The Company has no obligation to
redeem or purchase any Debentures pursuant to any sinking fund or analogous
requirement or upon the happening of a specified event or at the option of a
Holder thereof.

     Section 2.11. Defeasance and Covenant Defeasance.  Pursuant to Section
1301 of the Indenture, the Company hereby designates the Debentures as
defeasible pursuant to Section 1302 (relating to defeasance and discharge) and
Section 1303 (relating to covenant defeasance) of the Indenture.

     Section 2.12. Immediately Available Funds.  All payments of principal and
interest on the Debentures shall be made in immediately available funds.

     Section 2.13. Priority of Debentures.  The Debentures shall rank pari
passu with the 2097 Senior Debentures.


                                  ARTICLE III

                                    Expenses

     Section 3.1. Payment of Expenses.  In connection with the offering, sale
and issuance of the Debentures, the Company, in its capacity as borrower with
respect to the Debentures, shall pay all costs and expenses relating to the
offering, sale and issuance of the Debentures, including commissions to the
underwriters payable pursuant to the Underwriting Agreement and compensation
and expenses of the Trustee under the Indenture in accordance with the
provisions of Section 607 of the Indenture.

     Section 3.2. Payment Upon Resignation or Removal.  Upon termination of
this Second Supplemental Indenture or the Indenture or the removal or
resignation of the Trustee, unless otherwise stated, the Company shall pay to
the Trustee all amounts accrued to the date of such termination, removal or
resignation.


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                                   ARTICLE IV

                            Miscellaneous Provisions

     Section 4.1. Trustee Not Responsible for Recitals.  The recitals herein
contained are made by the Company and not by the Trustee, and the Trustee
assumes no responsibility for the correctness thereof.  The Trustee makes no
representation as to the validity or sufficiency of this Second Supplemental
Indenture.

     Section 4.2.  Adoption, Ratification and Confirmation.  The Indenture, as
supplemented and amended by this Second Supplemental Indenture, is in all
respects hereby adopted, ratified and confirmed.

     Section  4.3.  Counterparts.  This Second Supplemental Indenture may be
executed in any number of counterparts, each of which shall be an original, but
such counterparts shall together constitute but one and the same instrument.

     Section 4.4. GOVERNING LAW.  THIS SECOND SUPPLEMENTAL INDENTURE AND EACH
DEBENTURE SHALL BE GOVERNED BY AND CONSTRUED IN ACCORDANCE WITH THE INTERNAL
LAWS OF THE STATE OF NEW YORK.


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     IN WITNESS WHEREOF, the parties hereto have caused this Second
Supplemental Indenture to be duly executed, and their respective corporate
seals to be hereunto affixed and attested, on the date or dates indicated in
the acknowledgments and as of the day and year first above written.


                                           THE ALLSTATE CORPORATION   
                                                                      
                                                                      
                                           By:______________________
                                           Name:                      
                                           Title:                     
                                                                      

ATTEST:


By:______________________
Name:
Title:


                                           STATE STREET BANK AND TRUST COMPANY,
                                           as Trustee
                                      
                                      
                                      
                                           By:______________________
                                           Name:
                                           Title:




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                                                                       EXHIBIT A

                           (FORM OF FACE OF SECURITY)

     This Security is a Global Security within the meaning of the Indenture
hereinafter referred to and is registered in the name of a Depositary or a
nominee of a Depositary.  This Security is exchangeable for Securities
registered in the name of a person other than the Depositary or its nominee
only in the limited circumstances described in the Indenture, and no transfer
of this Security (other than a transfer of this Security as a whole by the
Depositary to a nominee of the Depositary or by a nominee of the Depositary to
the Depositary or another nominee of the Depositary) may be registered except
in limited circumstances.

     Unless this Security is presented by an authorized representative of The
Depository  Trust Company (55 Water Street, New York, New York) to the issuer
or its agent for registration of transfer, exchange or payment, and any
Security issued is registered in the name of Cede & Co. or such other name as
requested by an authorized representative of The Depository Trust Company and
any payment hereon is made to Cede & Co., ANY TRANSFER, PLEDGE OR OTHER USE
HEREOF FOR VALUE OR OTHERWISE BY A PERSON IS WRONGFUL since the registered
owner hereof, Cede & Co., has an interest herein.

Certificate No.                                                   $_____________
                                                            CUSIP No.  _________

                            THE ALLSTATE CORPORATION

                        __ % Senior Debentures due ____

     THE ALLSTATE CORPORATION, a Delaware corporation (the "Company," which
term includes any successor corporation under the Indenture hereinafter
referred to), for value received, hereby promises to pay to CEDE & CO. or
registered assigns, the principal sum of ____________ ($__________) on May 15,
____.  The Company further promises to pay interest on said principal sum
outstanding from May 26, 1998, or from the most recent interest payment date
(each such date, an "Interest Payment Date") to which interest has been paid or
duly provided for, semiannually in arrears on May 15 and November 15 of each
year commencing November 15, 1998, at the rate of ___% per annum, until the
principal hereof shall have become due and payable and, until the principal
hereof is paid or duly provided for or made available for payment.   The amount 
of interest payable on any Interest Payment Date shall be computed on the basis
of a 360-day year of twelve 30-day months.  The amount of interest payable for
any partial period shall be computed on the basis of the number of actual days
elapsed in a 360-day year of twelve 30-day months.  In the event that any date
on which interest is payable on this Security is not a Business Day, then
payment of interest payable on such date will be made on the next succeeding day
that is a Business Day (and without any interest or other payment in respect of
any such delay).  A "Business Day" shall mean any day, other than a Saturday or
Sunday, on which the banks in the City of New York are not


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required by law to close.  The interest installment so payable, and punctually
paid or duly provided for, on any Interest Payment Date will, as provided in
the Indenture, be paid to the Person in whose name this Security (or one or
more Predecessor Securities) is registered at the close of business on the
preceding April 30, if the Interest Payment Date is May 15, or October 31, if
the Interest Payment Date is November 15 (a "Regular Record Date").  Any such
interest installment not punctually paid or duly provided for shall forthwith
cease to be payable to the registered Holder on such Regular Record Date and
may either be paid to the Person in whose name this Security (or one or more
Predecessor Securities) is registered at the close of business on a Special
Record Date to be fixed by the Trustee for the payment of such Defaulted
Interest, notice whereof shall be given to the Holder of this Security not less
than 10 days prior to such Special Record Date, or be paid at any time in any
other lawful manner not inconsistent with the requirements of any securities
exchange on which this Security may be listed, and upon such notice as may be
required by such exchange, all as more fully provided in the Indenture.

     The principal of (and premium, if any) and the interest on this Security
shall be payable at the office or agency of the Company maintained for that
purpose in the United States in such coin or currency of the United States of
America that at the time of payment is legal tender for payment of public and
private debts; provided, however, that payment of interest may be made  at the
option of the Company by check mailed to the registered Holder at such address
as shall appear in the Security Register.  Notwithstanding the foregoing, so
long as the Holder of this Security is The Depository Trust Company (or its
nominee, including, without limitation, Cede & Co.), the payment of the
principal of (and premium, if any) and interest on this Security will be made
at such place and to such account as may be designated by The Depository Trust
Company (or its nominee, including, without limitation, Cede & Co.).  All
payments of principal and interest hereunder shall be made in immediately
available funds.

     Reference is hereby made to the further provisions of this Security set
forth below, which further provisions shall for all purposes have the same
effect as if set forth at this place.

     Unless the certificate of authentication hereon has been executed by the
Trustee by manual signature, this Security shall not be entitled to any benefit
under the Indenture or be valid for any purpose.


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     IN WITNESS WHEREOF, the Company has caused this instrument to be executed.

                                     THE ALLSTATE CORPORATION   
                                                                
                                                                
                                                                
                                     By:______________________      
                                     Name:                      
                                     Title:                     
                                                                
                                                                

Attest:



By:___________________________________
      Name:
     Title:

                         CERTIFICATE OF AUTHENTICATION

     This is one of the Securities of the series designated herein referred to
in the within-mentioned Indenture.

Dated:

STATE STREET BANK AND TRUST COMPANY,
as Trustee



By:______________________
     Authorized Signatory



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                         (FORM OF REVERSE OF SECURITY)

     This Security is one of a duly authorized issue of a series of Securities
of the Company, designated as its __% Senior Debentures due ___, issued under
and pursuant to an Indenture, dated as of December 16, 1997 between the Company
and State Street Bank and Trust Company, as Trustee (herein called the
"Trustee," which term includes any successor trustee under the Indenture), as
supplemented by the First Supplemental Indenture, dated as of December 16, 1997
between the Company and the Trustee and the Second Supplemental Indenture,
dated as of May 20, 1998, between the Company and the Trustee (the Indenture as
so supplemented, the "Indenture"), to which Indenture and all indentures
supplemental thereto reference is hereby made for a description of the rights,
limitations of rights, obligations, duties and immunities thereunder of the
Trustee, the Company and the Holders of this Security and the other Securities
of this series, and of the terms upon which this Security and the other
Securities of this series are, and are to be, authenticated and delivered.

     All terms used in this Security that are defined in the Indenture shall
have the meanings assigned to them in the Indenture.

     If an Event of Default with respect to Securities of this series shall
occur and be continuing, the principal of the Securities of this series may be
declared due and payable in the manner, with the effect and subject to the
conditions provided in the Indenture.

     The Indenture contains provisions for satisfaction, discharge and
defeasance at any time of the entire indebtedness of this Security upon
compliance by the Company with certain conditions set forth in the Indenture.
Pursuant to Section 1301 of the Indenture, the Company has designated this
Security as being defeasible pursuant to Section 1302 and Section 1303 of the
Indenture.

     The Indenture permits, with certain exceptions as therein provided, the
amendment thereof and the modification of the rights and obligations of the
Company and the rights of the Holders of the Securities of each series to be
affected under the Indenture at any time by the Company and the Trustee with 
the consent of the Holders of a majority in principal amount of the Securities
of each series at the time Outstanding of each series to be affected.  The
Indenture also contains provisions permitting Holders of specified percentages
in principal amount of the Securities of each series at the time Outstanding,
on behalf of the Holders of all Securities of such series, to waive compliance
by the Company with certain provisions of the Indenture and certain past
defaults under the Indenture and their consequences.  Any such consent or waiver
by the Holder of this Security shall be conclusive and binding upon such Holder
and upon all future Holders of this Security and of any Security issued upon the
registration of transfer hereof or in exchange therefor or in lieu hereof,
whether or not notation of such consent or waiver is made upon this Security.


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     No reference herein to the Indenture and no provision of this Security or
of the Indenture (other than Section 1302 and Section 1303 of the Indenture)
shall alter or impair the obligation of the Company to pay the principal and
interest on this Security at the times, place and rate, and in the coin or
currency, herein prescribed.

     As provided in the Indenture and subject to certain limitations therein
set forth, the transfer of this Security is registrable in the Securities
Register, upon surrender of this Security for registration of transfer at the
office or agency of the Company maintained under Section 1002 of the Indenture
duly endorsed by, or accompanied by a written instrument of transfer, in form
satisfactory to the Company and the Securities Registrar, duly executed by the
Holder hereof or his or her attorney duly authorized in writing, and thereupon
one or more new Securities of this series, of authorized denominations and for
the same aggregate principal amount, will be issued to the designated
transferee or transferees.  No service charge shall be made for any such
registration of transfer or exchange, but the Company may require payment of a
sum sufficient to cover any tax or other governmental charge payable in
connection therewith.

     Prior to due presentment of this Security for registration of transfer,
the Company, the Trustee and any agent of the Company or the Trustee may treat
the Person in whose name this Security is registered as the owner hereof for
all purposes, whether or not this Security be overdue, and neither the Company,
the Trustee nor any such agent shall be affected by notice to the contrary.

     This Global Security is exchangeable for Securities of this series in
definitive form only under certain limited circumstances set forth in the
Indenture.  Securities of this series so issued are issuable in book-entry form
only and in denominations of $1,000 and any integral multiple thereof.  As
provided in the Indenture and subject to certain limitations herein and therein
set forth, Securities of this series so issued are exchangeable for a like
aggregate principal amount of Securities of this series of a different
authorized denomination, as requested by the Holder surrendering the same.

     The Company and, by its acceptance of this Security or a beneficial
interest therein, the Holder of, and any Person that acquires a beneficial
interest in, this Security agree that for United States federal, state and
local tax purposes it is intended that this Security constitute indebtedness.

     THIS SECURITY SHALL BE GOVERNED BY AND CONSTRUED IN ACCORDANCE WITH THE
INTERNAL LAWS OF THE STATE OF NEW YORK.



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