EXHIBIT 1.1


                         ARIZONA PUBLIC SERVICE COMPANY

                              FIRST MORTGAGE BONDS


                             UNDERWRITING AGREEMENT

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Dear Sir or Madam:

     1.  INTRODUCTION.  Arizona Public Service Company,  an Arizona  corporation
(the "Company"), proposes to issue and sell from time to time up to $525,000,000
in  aggregate  principal  amount  of its  First  Mortgage  Bonds  (the  "Bonds")
registered  under the registration  statements  referred to in Section 2(a). The
Bonds will be issued  under its  Mortgage  and Deed of Trust dated as of July 1,
1946, to The Bank of New York, as successor Trustee, as amended and supplemented
by fifty-five indentures  supplemental thereto (the "Mortgage"),  and as further
amended  and  supplemented  by one or more  additional  Supplemental  Indentures
relating to the Bonds (the  "Supplemental  Indentures") (the Mortgage as amended
and supplemented by such  Supplemental  Indentures  being sometimes  hereinafter
referred to as the "Indenture"). The Bonds will be issued in one or more series,
which series may vary as to interest rates,  maturities,  redemption provisions,
selling prices, and other terms, with all such terms for any particular issue of
the Bonds being determined at the time of sale.  Particular  issues of the Bonds
may be sold from time to time to one or more of the firms to whom this Agreement
is addressed, and to such other purchasers as the Company shall designate and as
shall  agree  in  writing  to  comply  with the  terms  and  conditions  of this
Agreement, for resale in accordance with the terms of offering determined at the
time of sale. The Bonds involved in any such offering are  hereinafter  referred
to as the  "Purchased  Bonds," the parties  that agree to purchase  the same are
hereinafter  referred to as the  "Underwriters" of such Purchased Bonds, and the
representative or  representatives  of the Underwriters,  if any, specified in a
Terms  Agreement  referred  to in Section 3 are  hereinafter  referred to as the
"Representatives."

     2.  REPRESENTATIONS  AND WARRANTIES OF THE COMPANY. In connection with each
offering of the Purchased  Bonds,  the Company  represents  and warrants to, and
agrees with, the several Underwriters that:

          (a) A registration  statement (No.  333-58445) relating to $25,000,000
     of  the  Bonds,   unsecured  debentures,   notes,  or  other  evidences  of
     indebtedness  (the  "Securities"),  or the  Company's  senior  notes  and a
     registration statement (No. 333-____) relating to $500,000,000 of the Bonds
     or  Securities   (including  a  combined   prospectus  relating  to  up  to
     $525,000,000 of the Bonds or Securities) were filed with the Securities and
     Exchange  Commission (the  "Commission")  and have become  effective.  Such
     registration  statements,  as  each is  amended  at the  time of the  Terms
     Agreement  referred to in Section 3 relating to the  Purchased  Bonds,  are
     hereinafter  referred  to as the  "First  Registration  Statement"  and the
     "Second  Registration  Statement,"  respectively,  and,  together  with any
     related  Rule 462(b)  registration  statement  or  amendment  thereto,  are
     hereinafter referred to collectively as the "Registration  Statements," and
     such  prospectus,  as  supplemented as contemplated by Section 3 to reflect
     the terms of the Purchased Bonds and terms of offering  thereof,  including
     all material  incorporated by reference therein, is hereinafter referred to
     as the "Prospectus."

          (b) Each part of the  Registration  Statements  relating to the Bonds,
     when such part became effective,  conformed in all material respects to the
     requirements of the Securities Act of 1933 (the "Act"), the Trust Indenture
     Act of 1939 (the "Trust  Indenture Act") and the rules and regulations (the
     "Rules and  Regulations")  of the Commission and did not include any untrue
     statement of a material fact or omit to state any material fact required to
     be  stated  therein  or  necessary  to  make  the  statements  therein  not
     misleading,  and on the date of each Prospectus  Supplement  referred to in
     Section 3, the  Registration  Statements and the Prospectus will conform in
     all material  respects to the  requirements of the Act, the Trust Indenture
     Act and the Rules and Regulations,  and at such date none of such documents
     will include any untrue  statement of a material  fact or omit to state any
     material  fact  required  to be stated  therein  or  necessary  to make the
     statements therein not misleading;  provided,  however,  that the foregoing
     does not apply to (a)  statements in or omissions  from any such  documents
     based upon written information  furnished to the Company by any Underwriter
     specifically  for  use  therein  or  (b)  that  part  of  the  Registration
     Statements that consists of the Statement of Eligibility and  Qualification
     (Form T-1) under the Trust  Indenture  Act of 1939 of The Bank of New York,
     as successor Trustee under the Mortgage.

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          (c) An order of the  Arizona  Corporation  Commission  shall have been
     granted   authorizing  the  execution  and  delivery  of  the  Supplemental
     Indenture  relating to the Purchased Bonds and the issuance and sale of the
     Purchased  Bonds on the terms and  conditions  herein and in the Prospectus
     and the Terms Agreement  referred to in Section 3 relating to the Purchased
     Bonds,  and the approval or consent of no other public body or authority is
     necessary to the execution and delivery of such  Supplemental  Indenture or
     the validity of the issuance and sale of the Purchased Bonds, except as may
     be required under state securities or blue sky laws.

          (d) Except for  property  specifically  excepted  from the lien of the
     Indenture or released  therefrom in accordance with the terms thereof,  the
     Company  has good and  marketable  title in fee  simple,  except  for items
     described in (A), (B), and (C) below, to all of the real property purported
     in the Indenture to be so held, good and valid  leasehold  interests in all
     properties  purported in the Indenture to be held under lease, and good and
     valid title to all other  properties  described in the Indenture as subject
     to the lien thereof (which  property  excludes (i) the combined cycle plant
     referred to in Note 9 of Notes to  Financial  Statements  in the  Company's
     Form 10-K  Report for the fiscal  year ended  December  31, 1998 (the "1998
     Form 10-K Report") incorporated by reference in the Registration Statements
     but includes the Company's  leasehold  and related  interests in that plant
     and (ii)  certain  leased  interests  in Unit 2 of the Palo  Verde  Nuclear
     Generating  Station referred to in Note 9 of Notes to Financial  Statements
     in  the  1998  Form  10-K  Report),   except  that  the   transmission  and
     distribution  lines of the Company,  other than those located on land owned
     in fee by the Company,  and the property described in Section 15 of Article
     IV of the Forty-first Supplemental Indenture, have been installed in public
     streets or alleys and in highways under  ordinances and permits  granted by
     the  various  governmental  bodies  having   jurisdiction,   or  have  been
     constructed on leaseholds,  easements or rights-of-way  granted, with minor
     exceptions,  by the apparent  owners of record of the land and such leases,
     easements,  or rights-of-way  are subject to any defects in or encumbrances
     on the title of the  respective  lessors of such leases or grantors of such
     easements or  rights-of-way;  title to the aforesaid  properties is subject
     only to: (A) the lien of the Mortgage, (B) Excepted Encumbrances as defined
     in the  Mortgage,  and (C) other liens,  encumbrances  or defects,  none of
     which,  individually  or in the  aggregate,  materially  interfere with the
     business or operations of the Company (with respect to leasehold  interests

                                       3

     on the Navajo  Reservation,  this  representation  is intended and shall be
     understood  to mean  only  that the  Company  is the  owner  of the  rights
     conferred upon it by the leases from the Navajo Tribe relating to the sites
     on which the Navajo Plant and the Four Corners Plant are located,  and that
     while the Company is not aware of the assertion of any claim contesting the
     interest of the Navajo Tribe in the lands leased, the Company does not give
     any representation  with respect to the interest of the Navajo Tribe in the
     lands leased or with respect to the  enforceability  of such leases against
     the Navajo  Tribe);  the Mortgage,  subject only as above set forth in this
     clause, now constitutes,  and the Mortgage and the Supplemental  Indentures
     theretofore executed,  subject only as above set forth in this clause, when
     the  latter  shall have been duly  recorded  and  filed,  will  constitute,
     together and as a single instrument, a direct and valid first mortgage lien
     upon said  properties,  which include all of the  properties of the Company
     (other  than the  classes or items of  property  expressly  excepted in the
     Mortgage);  and all properties (other than the classes or items of property
     expressly  excepted in the  Mortgage or  expressly  released  from the lien
     thereof)  acquired  by the  Company  after  the  date  of the  Supplemental
     Indenture  relating to the Purchased  Bonds in each county in the States of
     Arizona and New Mexico in which the Mortgage and the Supplemental Indenture
     shall have been duly recorded and filed (and, as to which properties,  with
     respect to priority only, any necessary  recordation and/or filing has been
     accomplished,    including   therein   any   necessary    descriptions   of
     after-acquired  real property and real  property upon which  after-acquired
     fixtures are affixed) will,  upon such  acquisition,  become subject to the
     first mortgage lien thereof, subject, however, to Excepted Encumbrances and
     to liens, if any, existing or placed thereon at the time of the acquisition
     thereof by the Company and,  with respect to priority  only,  to liens,  if
     any, existing prior to the time of any necessary  recordation and/or filing
     by the Company.

          (e)  The  Company  holds  such  valid   franchises,   certificates  of
     convenience  and  necessity,  licenses,  and permits as are necessary  with
     respect to the  maintenance  and  operation of its property and business as
     now  conducted,  except that (A) the Company  from time to time makes minor
     extensions   of  its  system  prior  to  the  time  a  related   franchise,
     certificate,  license,  or  permit  is  procured,  (B)  from  time  to time
     communities  already being served by the Company  become  incorporated  and
     considerable  time may elapse  before a franchise is procured,  (C) certain
     franchises  may have expired prior to the  renegotiation  thereof,  (D) the
     Company may not have obtained certain permits or variances  relating to the
     environmental  requirements  described in any of its Form 10-K Report,  its
     Form 10-Q Reports, and/or its Form 8-K Reports incorporated by reference in

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     the Registration  Statements,  (E) certain minor defects and exceptions may
     exist which,  individually  and in the aggregate,  are not deemed material,
     and  (F) the  Company  does  not  make  any  representation  regarding  the
     geographical scope of any franchise,  certificate,  license, or permit that
     is not specific as to its geographical scope.

     3. PURCHASE AND OFFERING.  The obligation of the  Underwriters to purchase,
and the obligation of the Company to sell, the Purchased Bonds will be evidenced
by an exchange of facsimile  transmission or other written  communications  (the
"Terms  Agreement")  at the time the Company  determines  to sell the  Purchased
Bonds.  The Terms  Agreement  shall  specify (by  incorporation  by reference or
otherwise)  the parties that will be  Underwriters,  the principal  amount to be
purchased  by  each,  the  purchase  price to be paid by the  Underwriters,  any
compensation or commissions to be paid to Underwriters,  the offering price, and
the  terms of the  Purchased  Bonds  not  already  specified  in the  Indenture,
including, but not limited to, interest rates, maturity,  redemption provisions,
and sinking fund  requirements,  if any. The Terms  Agreement shall also specify
(by  incorporation  by reference or otherwise) the time and date of delivery and
payment (the "Closing Date"), the place of delivery and payment, and any details
of the terms of offering that should be reflected in the  prospectus  supplement
relating to the offering of the Purchased Bonds (the  "Prospectus  Supplement").
It is understood that the  Underwriters  will offer the Purchased Bonds for sale
as set forth in the Prospectus.  The obligations of the Underwriters to purchase
the Purchased  Bonds shall be several and not joint.  Except as may otherwise be
set forth in the Terms Agreement, the Purchased Bonds will be in definitive form
and in such  denominations  and registered in such names as the Underwriters may
request.

     4. COVENANTS OF THE COMPANY.  In connection with each offering of Purchased
Bonds, the Company covenants and agrees with the several Underwriters that:

          (a) The Company will advise the  Underwriters  or the  Representatives
     promptly  of  any  proposed  amendment  or  supplementation  of  the  First
     Registration   Statement,   the  Second  Registration   Statement,  or  the
     Prospectus.   The  Company  will  also  advise  the   Underwriters  or  the
     Representatives  of the  institution  by the  Commission  of any stop order
     proceedings  in respect  of the First  Registration  Statement,  the Second
     Registration  Statement,  or of any  part  thereof,  and  will use its best
     efforts to  prevent  the  issuance  of any such stop order and to obtain as
     soon as possible its lifting, if issued.

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          (b) If, at any time when a prospectus  relating to the Purchased Bonds
     is required to be delivered  under the Act, any event occurs as a result of
     which the  Prospectus  as then  amended or  supplemented  would  include an
     untrue  statement of a material  fact,  or omit to state any material  fact
     necessary to make the statements therein, in the light of the circumstances
     under which they were made,  not  misleading,  or if it is necessary at any
     time to amend or supplement the First  Registration  Statement,  the Second
     Registration  Statement,  or the  Prospectus  to comply  with the Act,  the
     Company  promptly will prepare and file with the Commission an amendment or
     supplement  that will  correct  such  statement or omission or an amendment
     that will effect such compliance.

          (c) As soon as  practicable,  but not later than 18 months,  after the
     date of the Terms Agreement  relating to the Purchased  Bonds,  the Company
     will make generally  available to its  securityholders an earning statement
     or statements  (which need not be audited) covering a period of at least 12
     months  beginning  after  the  effective  date of the  Second  Registration
     Statement (as defined in Rule 158(c) under the Act), which will satisfy the
     provisions  of  Section  11(a)  of the Act and the  rules  and  regulations
     thereunder.

          (d)  The   Company   will   furnish   to  the   Underwriters   or  the
     Representatives such copies of the Registration  Statements  (including one
     copy of the Second Registration  Statement for each Representative,  or for
     each Underwriter if there are no  Representatives,  and for the counsel for
     the Underwriters,  which is signed and includes all exhibits),  any related
     preliminary  prospectus  supplements  and  the  Prospectus,  including  all
     amendments  or  supplements  to  such  documents,   as  may  be  reasonably
     requested.

          (e) The Company  will arrange or  cooperate  in  arrangements  for the
     qualification  of the  Purchased  Bonds for sale and the  determination  of
     their  eligibility for investment  under the laws of such  jurisdictions as
     the  Underwriters or the  Representatives  designate and will continue such
     qualifications  in effect so long as required for the  distribution  of the
     Purchased Bonds, provided that the Company shall not be required to qualify
     as a foreign  corporation in any State, to consent to service of process in
     any State other than with respect to claims  arising out of the offering or
     sale of the Purchased Bonds, or to meet other requirements  deemed by it to
     be unduly burdensome.

          (f)  During  the  period  of five  years  after  the date of the Terms
     Agreement  relating to the Purchased Bonds, the Company will furnish to the
     Underwriters or the Representatives  thereunder, and, upon request, each of
     the other  Underwriters,  (i) as soon as practicable  after the end of each

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     fiscal year, a balance sheet and statements of income and retained earnings
     of the Company as at the end of and for such year, all in reasonable detail
     and certified by independent  public  accountants,  and (ii) (A) as soon as
     practicable  after the end of each quarterly  fiscal period (except for the
     last  quarterly  fiscal  period of each fiscal  year),  a balance sheet and
     statement  of income of the  Company as at the end of and for such  period,
     all  in  reasonable  detail  and  certified  by a  principal  financial  or
     accounting officer of the Company, (B) as soon as available, a copy of each
     report of the Company mailed by the Company to  stockholders  or filed with
     the  Commission,  and  (C)  from  time  to  time,  such  other  information
     concerning  the  Company as may  reasonably  be  requested.  So long as the
     Company has active  subsidiaries,  such financial  statements  will be on a
     consolidated  basis to the  extent  the  accounts  of the  Company  and its
     subsidiaries are consolidated.

          (g) The Company will pay all expenses  incident to the  performance of
     its obligations  under this Agreement,  and will reimburse the Underwriters
     for any reasonable expenses (including reasonable fees and disbursements of
     counsel)  incurred  by them in  connection  with the  qualification  of the
     Purchased Bonds with respect to which the Terms  Agreement  relating to the
     Purchased Bonds has been entered for sale, and the  determination  of their
     eligibility for  investment,  under the laws of such  jurisdictions  as the
     Representatives  or,  if there  are no  Representatives,  the  Underwriters
     designate, and the printing of memoranda relating thereto, and for any fees
     charged by  investment  rating  agencies  for the  rating of the  Purchased
     Bonds.

          (h) The Company will not offer or sell any of its First Mortgage Bonds
     for a period  beginning  at the time of  execution  of the Terms  Agreement
     relating to the  Purchased  Bonds and ending on the Closing  Date  relating
     thereto without prior consent of the Underwriters or the Representatives.

     5.  CONDITIONS OF THE OBLIGATIONS OF THE  UNDERWRITERS.  The obligations of
the several  Underwriters  to purchase and pay for the  Purchased  Bonds will be
subject to the accuracy of the representations and warranties on the part of the
Company  herein,  to the accuracy of the  statements  of Company  officers  made
pursuant to the  provisions  hereof,  to the  performance  by the Company of its
obligations hereunder, and to the following additional conditions precedent:

          (a) The  Underwriters  or the  Representatives  shall have  received a
     letter from DELOITTE & TOUCHE LLP,  dated the date of the Terms  Agreement,
     confirming that they are independent  certified public  accountants  within
     the meaning of the Act and the applicable  published  Rules and Regulations

                                       7

     thereunder,  and stating in effect that (i) in their  opinion the financial
     statements and schedules of the Company  examined by them and  incorporated
     by  reference  in the  Registration  Statements  comply  as to  form in all
     material  respects  with  the  applicable  accounting  requirements  of the
     Securities  Exchange Act of 1934 (the "1934 Act") and the  published  Rules
     and Regulations thereunder and (ii) on the basis of a reading of the latest
     available  interim  financial  statements  of  the  Company,  inquiries  of
     officials of the Company  responsible for financial and accounting matters,
     and other specified procedures, nothing came to their attention that caused
     them to believe that (A) the unaudited financial statements incorporated by
     reference,  if any, in the Registration Statements do not comply as to form
     in all material respects with the applicable accounting requirements of the
     1934 Act and the  published  Rules and  Regulations  thereunder  or are not
     stated  on a  basis  substantially  consistent  with  that  of the  audited
     financial   statements   incorporated  by  reference  in  the  Registration
     Statements,  (B) at  the  date  of  the  most  recent  available  unaudited
     financial  statements and at a specified date not more than five days prior
     to the date of this  Agreement,  there was any  increase  in the amounts of
     common stock, redeemable preferred stock, or non-redeemable preferred stock
     of the Company or any increase, exceeding $10,000,000, in long-term debt of
     the  Company  or,  at the  date  of the  most  recent  available  unaudited
     financial  statements there was any decrease in net assets as compared with
     amounts  shown in the most  recent  financial  statements  incorporated  by
     reference  in the  Registration  Statements,  or (C) for  the  twelve-month
     period ended at the date of the most recent available  unaudited  financial
     statements  there were any  decreases,  exceeding  3%, as compared with the
     twelve-month  period  ended  at the  date  of  the  most  recent  financial
     statements incorporated by reference in the Registration Statements, in the
     amounts of total revenues or net income,  except in all cases for increases
     or decreases which result from the declaration or payment of dividends,  or
     which the Registration  Statements  (including any material incorporated by
     reference  therein)  disclose  have  occurred  or may  occur,  or which are
     described in such letter.

          (b)  No  stop  order   suspending  the   effectiveness  of  the  First
     Registration  Statement,  the Second  Registration  Statement,  or any part
     thereof  shall have been issued and no  proceedings  for that purpose shall
     have  been   instituted  or,  to  the  knowledge  of  the  Company  or  the
     Underwriters, shall be contemplated by the Commission.

          (c) Subsequent to the execution of the Terms Agreement relating to the
     Purchased  Bonds,  (i) there shall not have  occurred  any  change,  or any

                                       8

     development  involving a prospective  change, in or affecting  particularly
     the business or properties of the Company or its subsidiaries which, in the
     judgment of a majority in  interest  of the  Underwriters  under such Terms
     Agreement, including any Representatives, materially impairs the investment
     quality  of the  Purchased  Bonds,  (ii)  there  shall not have  occurred a
     suspension or material limitation in trading in securities generally on the
     New York Stock  Exchange,  (iii)  there  shall not have  occurred a general
     moratorium on commercial  banking activities in New York declared by either
     Federal  or New  York  State  authorities,  (iv)  no  rating  of any of the
     Company's debt securities shall have been lowered and there shall have been
     no public  announcement  that any such debt  securities have been placed on
     CreditWatch,  Watchlist,  or under any similar  surveillance or review,  in
     each case with negative implications,  by any recognized rating agency, and
     (v) there  shall not have  occurred  any  outbreak or  escalation  of major
     hostilities in which the United States is involved,  any declaration of war
     by Congress or any other substantial national or international  calamity or
     emergency if, in the judgment of a majority in interest of the Underwriters
     under such Terms Agreement,  including any  Representatives,  the effect of
     any such outbreak, escalation,  declaration, calamity or emergency makes it
     impractical or  inadvisable  to proceed with  completion of the sale of and
     payment for the Purchased Bonds.

          (d) The  Underwriters  or the  Representatives  shall have received an
     opinion  of Snell & Wilmer  L.L.P.,  counsel  for the  Company,  dated  the
     relevant Closing Date, to the effect that:

               (i)  The  Company  is  a  corporation  duly  organized,   validly
          existing,  and in good standing under the laws of the State of Arizona
          and has full corporate power and authority to carry on its business as
          presently  conducted;  and the Company is duly  qualified as a foreign
          corporation  to do business  and is in good  standing in the States of
          New Mexico,  California,  Oregon,  Washington,  Montana,  Wyoming, and
          Texas,  the  only  other  jurisdictions  in  which  it owns or  leases
          substantial  properties  or in  which  the  conduct  of  its  business
          requires such qualification;

               (ii) The  Purchased  Bonds have been duly  authorized,  executed,
          authenticated,  issued,  and delivered,  constitute  valid and legally
          binding  obligations  of the  Company  entitled  to the  benefits  and
          security  provided by the Indenture (except as the same may be limited
          by (a)  general  principles  of equity or by  bankruptcy,  insolvency,
          reorganization,  arrangement,  moratorium,  or other laws or equitable
          principles  relating to or affecting  the  enforcement  of  creditors'
          rights  generally or the  enforcement of the security  provided by the
          Indenture,  (b)  the  necessity  for  compliance  with  the  statutory
          procedural  requirements  governing  the  exercise  of  remedies  by a
          secured  creditor,  and (c) the  qualification  that certain  waivers,
          procedures,  remedies, and other provisions of the Purchased Bonds and
          the Indenture may be unenforceable  under or limited by the law of the
          State of Arizona; however, such law does not in such counsel's opinion
          substantially  prevent  the  practical  realization  of  the  benefits
          intended by such documents) and conform to the description  thereof in
          the Prospectus;

               (iii) The  Indenture  has been  duly  authorized,  executed,  and
          delivered,  has been duly qualified under the Trust Indenture Act, and
          constitutes a valid and binding  instrument  enforceable in accordance
          with  its  terms  except  as the same may be  limited  by (a)  general
          principles  of equity or by  bankruptcy,  insolvency,  reorganization,
          arrangement,   moratorium,  or  other  laws  or  equitable  principles
          relating  to  or  affecting  the  enforcement  of  creditors'   rights
          generally  or  the  enforcement  of  the  security   provided  by  the
          Indenture,  (b)  the  necessity  for  compliance  with  the  statutory
          procedural  requirements  governing  the  exercise  of  remedies  by a
          secured  creditor,  and (c) the  qualification  that certain  waivers,
          procedures,

                                       9

          remedies,  and  other  provisions  of  the  Purchased  Bonds  and  the
          Indenture  may be  unenforceable  under or  limited  by the law of the
          State of Arizona; however, such law does not in such counsel's opinion
          substantially  prevent  the  practical  realization  of  the  benefits
          intended by such documents;

               (iv) Except for property  specifically  excepted from the lien of
          the  Indenture  or released  therefrom  in  accordance  with the terms
          thereof,  the  Company  has good and  marketable  title in fee simple,
          except for items  described in (A), (B), and (C) below,  to all of the
          real property and fixtures thereon purported in the Indenture to be so
          held and that are both  located in the State of Arizona and  described
          in those title reports covering at least the Saguaro,  Yucca,  Cholla,
          Ocotillo,  West Phoenix, and Palo Verde plant sites that are listed on
          an exhibit to such  opinion  (the "Title  Documents")  (in giving such
          opinion, such counsel may rely solely upon the Title Documents and may
          assume the  accuracy  thereof  and of the real  property  descriptions
          contained therein and may state that no other investigation or inquiry
          has been made  with  respect  thereto),  and in  giving  the  opinions
          described below with respect to any liens,  defects,  and encumbrances
          on such title to such personal property,  such counsel may assume that
          the Company has good and valid title to all of the  personal  property
          located in the State of Arizona  and  described  in the  Indenture  as
          subject  to  the  lien  thereof  (which  property  shall  not  include
          fixtures),  and such  counsel  may rely  solely  upon,  and assume the
          accuracy  of,  a  search  of the  Uniform  Commercial  Code  Financing
          Statements filed in the records of the Arizona  Secretary of State and
          may assume that there are no liens or other  encumbrances  on personal
          property  (as  used in the  Arizona  Uniform  Commercial  Code) of the
          Company  located  in the State of  Arizona  other  than liens or other
          encumbrances  that have been  perfected  by  filing  with the  Arizona
          Secretary of State under Arizona Revised Statutes  ("A.R.S.")  Section
          47-9401.A;  such  title  is  subject  only  to:  (A)  the  lien of the
          Mortgage,  (B) Excepted  Encumbrances as defined in the Mortgage,  and
          (C) other liens, encumbrances, or defects, none of which, individually
          or in the  aggregate,  in the  opinion  of  such  counsel,  materially
          interfere   with  the  business  or  operations  of  the  Company  (in
          determining  whether any such other  liens,  encumbrances,  or defects
          materially  interfere  with the business or operations of the Company,
          such  counsel  may rely  solely  upon a  certificate  of an officer or

                                       10

          engineer  of the Company  which shall be attached to such  opinion and
          such  opinion may state that no other  investigation  or inquiry  with
          respect  thereto has been made);  the Mortgage,  subject only as above
          set forth in this clause,  now  constitutes,  and the Mortgage and the
          Supplemental  Indentures  theretofore executed,  subject only as above
          set  forth in this  clause,  when the  latter  shall  have  been  duly
          recorded  and  filed,  will  constitute,  together  and  as  a  single
          instrument, a direct and valid first mortgage lien upon said property;
          and all  properties  (other  than the  classes  or  items of  property
          expressly excepted in the Mortgage or expressly released from the lien
          thereof)  acquired by the Company  after the date of the  Supplemental
          Indenture  relating to the Purchased Bonds in each county in the State
          of Arizona in which the Mortgage and the Supplemental  Indenture shall
          have been duly recorded and filed and, with respect to priority  only,
          any  necessary   recordation   and/or  filing  has  been  accomplished
          (including therein any necessary  descriptions of after-acquired  real
          property  and real  property  upon which  after-acquired  fixtures are
          affixed)  will,  upon such  acquisition,  become  subject to the first
          mortgage lien thereof,  subject, however, to Excepted Encumbrances and
          to  liens,  if any,  existing  or  placed  thereon  at the time of the
          acquisition thereof by the Company and, with respect to priority only,
          to  liens,  if  any,  existing  prior  to the  time  of any  necessary
          recordation and/or filing by the Company;

               (v) The Company is the owner of the rights  conferred  upon it by
          the leases  from the Navajo  Tribe  relating  to the site on which the
          Navajo  Plant is located  and while  such  counsel is not aware of the
          assertion of any claim contesting the title of the Navajo Tribe to the
          lands  leased,  such  counsel  shall not be  required  to express  any
          opinion  with respect to the interest of the Navajo Tribe in the lands
          leased or with respect to the  enforceability  of such leases  against
          the Navajo Tribe;

               (vi) With certain  exceptions,  a public  service  corporation is
          required to obtain  certificates of convenience and necessity from the
          Arizona  Corporation  Commission  under  A.R.S.  Section  40-281.A for
          construction  of  its  lines,  plant,  services,  or  systems,  or any
          extensions  thereof,  within  the  State  of  Arizona,  and to  obtain
          franchises   or  similar   consents  or  permits  from   counties  and
          incorporated  municipalities  under  A.R.S.  Section  40-283.A for the
          construction,  operation, and maintenance of transmission lines within

                                       11

          the State of Arizona;  to the best of such counsel's  knowledge  after
          due inquiry, the Company holds such valid franchises,  certificates of
          convenience  and  necessity,  consents,  and permits  pursuant to such
          statutory  provisions as are necessary with respect to the maintenance
          and  operation of its property and business as now  conducted,  except
          that (A) the Company from time to time makes minor  extensions  of its
          system prior to the time a related franchise, certificate, license, or
          permit is procured,  (B) from time to time  communities  already being
          served by the Company become  incorporated and  considerable  time may
          elapse before a franchise is procured, (C) certain franchises may have
          expired prior to the renegotiation  thereof, (D) certain minor defects
          and exceptions may exist which, individually and in the aggregate, are
          not deemed  material,  and (E) such  counsel  need not be  required to
          express any opinion regarding the geographical scope of any franchise,
          certificate,  license,  or  permit  that  is  not  specific  as to its
          geographical scope;

               (vii) The issuance and sale of the  Purchased  Bonds on the terms
          and conditions set forth or contemplated  herein and in the Prospectus
          and the  Terms  Agreement  relating  to the  Purchased  Bonds  and the
          execution and delivery of the Supplemental  Indenture  relating to the
          Purchased Bonds have been duly  authorized by the Arizona  Corporation
          Commission,  said Commission had jurisdiction in the premises,  and no
          further approval,  authorization, or consent of any other public board
          or body is necessary to the validity of such issuance and sale of such
          Purchased  Bonds or the  execution  and delivery of such  Supplemental
          Indenture,  except as may be required  under state  securities or blue
          sky laws,  as to which  laws such  counsel  shall not be  required  to
          express an opinion;

               (viii)   The  First   Registration   Statement   and  the  Second
          Registration  Statement have become  effective  under the Act, and, to
          the best of the  knowledge of such counsel,  no stop order  suspending
          the  effectiveness of the First  Registration  Statement or the Second
          Registration  Statement  has been issued and no  proceedings  for that
          purpose have been instituted or are pending or contemplated  under the
          Act,  and each part of the  Registration  Statements  relating  to the
          Bonds, when such part became effective, and the Prospectus,  as of the
          date of the  Prospectus  Supplement,  and each amendment or supplement
          thereto, as of their respective effective or issue dates,  complied as

                                       12

          to form in all material respects with the requirements of the Act, the
          Trust  Indenture Act, and the published  Rules and  Regulations;  such
          counsel  has no reason to  believe  that any part of the  Registration
          Statements,  when such part became effective, or the Prospectus, as of
          the date of the Prospectus  Supplement,  or as of the Closing Date, or
          any amendment or supplement thereto, as of their respective  effective
          or issue  dates,  or as of the  Closing  Date,  contained  any  untrue
          statement  of a material  fact or omitted to state any  material  fact
          required  to be stated  therein or  necessary  to make the  statements
          therein  not  misleading;   the   descriptions  in  the   Registration
          Statements  and  Prospectus  of  statutes,   legal  and   governmental
          proceedings and contracts, and other documents are accurate and fairly
          present  the  information  required  to be  shown;  and to the  actual
          knowledge  of those  persons in the  lawyer  group  described  in such
          opinion, there are no legal or governmental proceedings required to be
          described in the  Prospectus  that are not described as required,  nor
          any contracts or documents of a character  required to be described in
          the  Registration  Statements or Prospectus or to be filed as exhibits
          to the  Registration  Statements  that are not  described and filed as
          required  (it being  understood  that such  counsel  need  express  no
          opinion  as to  the  financial  statements  or  other  financial  data
          contained in the Registration Statements or the Prospectus); and

               (ix)  This  Agreement  and the  Terms  Agreement  have  been duly
          authorized, executed, and delivered by the Company.

     In giving  such  opinion,  (a) Snell & Wilmer  L.L.P.  may rely solely upon
certificates  of the  Company  as to any  factual  matters  upon  which any such
opinions  are based and may rely upon the  opinion  of  Keleher & McLeod,  P.A.,
referred to below,  as to all  matters  governed by the laws of the State of New
Mexico,  but the opinion of Snell & Wilmer L.L.P.  shall state that, though they
are members of the Arizona Bar and do not hold  themselves out as experts on the
laws of the  State of New  Mexico,  they  have  made a study of the laws of such
State  insofar  as such laws are  involved  in the  conclusions  stated in their
opinion, other than such laws as relate to matters of title, and from such study
it is their opinion that such laws support such  conclusions  and that, in their
opinion,  the Underwriters and they are justified to such extent in relying upon
the opinion of Keleher & McLeod,  P.A.;  and (b) the lawyer group referred to in
such opinion will mean those lawyers in the offices of Snell & Wilmer L.L.P. who

                                       13

(i) have billed any time on the  particular  transaction  to which such  opinion
relates or (ii) have  billed  more than ten hours to any  Company  matter in the
twelve-month  period  preceding  the date on which the list of such  lawyers was
compiled for purposes of inquiry pursuant to such opinion.

          (e) The  Underwriters  or the  Representatives  shall have received an
     opinion of Keleher & McLeod,  P.A.,  New Mexico  counsel  for the  Company,
     dated the Closing Date, to the effect that:

               (i) The Company is duly qualified as a foreign  corporation to do
          business  and is in good  standing  in the State of New Mexico and has
          full  corporate  power  and  authority  to  engage in the State of New
          Mexico in the business now conducted by it therein;

               (ii) The  activities of the Company in the State of New Mexico to
          date do not  constitute it a "public  utility" as that term is defined
          in the relevant laws of the State of New Mexico,  and accordingly,  no
          public utility franchises or certificates of convenience and necessity
          are necessary under New Mexico law with respect to the maintenance and
          operation of the  Company's  property and business as now conducted in
          the State of New Mexico and no approval,  authorization, or consent of
          the New Mexico Public Regulation  Commission or any other public board
          or body of the State of New Mexico is required  for the  issuance  and
          sale of the Purchased Bonds on the terms and conditions  herein and in
          the Prospectus set forth or  contemplated  or for the execution of the
          Supplemental  Indenture relating to the Purchased Bonds, except as may
          be required under New Mexico state  securities or blue sky laws, as to
          which laws such counsel shall not be required to express an opinion;

               (iii)  Assuming  that the Company has good and valid title to all
          of the  personal  property  located  in the  State of New  Mexico  and
          described  in the  Indenture  as  subject to the lien  thereof  (which
          property shall not include fixtures) ("Personal Property"),  in giving
          the opinions  described  below with respect to any liens,  defects and
          encumbrances on such title to such Personal Property, such counsel may
          rely solely upon,  and assume the accuracy of, a search of the Uniform
          Commercial Code Financing  Statements  filed in the records of the New
          Mexico  Secretary  of State and may assume  that there are no liens or
          other  encumbrances  on personal  property  (as used in the New Mexico

                                       14

          Uniform  Commercial  Code) of the Company  located in the State of New
          Mexico other than liens or other encumbrances that have been perfected
          by  filing  with  the New  Mexico  Secretary  of State  under  Section
          55-9-401,  New  Mexico  Statutes  Annotated  1978;  such title to such
          Personal  Property is subject  only to: (A) the lien of the  Mortgage,
          (B) Excepted  Encumbrances  as defined in the Mortgage,  and (C) other
          liens, encumbrances, or defects, none of which, individually or in the
          aggregate,  in the opinion of such counsel,  materially interfere with
          the business or operations of the Company (in determining  whether any
          such other liens,  encumbrances,  or defects materially interfere with
          the  business or  operations  of the  Company,  such  counsel may rely
          solely  upon a  certificate  of an officer or  engineer of the Company
          which  shall be attached  to such  opinion and such  opinion may state
          that no other  investigation  or inquiry with respect thereto has been
          made);  the Mortgage,  subject only as above set forth in this clause,
          now  constitutes,  and the  Mortgage and the  Supplemental  Indentures
          theretofore executed,  subject only as above set forth in this clause,
          when the  latter  shall  have  been  duly  recorded  and  filed,  will
          constitute,  together and as a single  instrument,  a direct and valid
          first  mortgage lien upon such Personal  Property;  and all properties
          (other than the classes or items of property expressly excepted in the
          Mortgage or expressly  released from the lien thereof) acquired by the
          Company after the date of the Supplemental  Indenture  relating to the
          Purchased Bonds in each county in the State of New Mexico in which the
          Mortgage and the Supplemental  Indenture shall have been duly recorded
          and  filed  and,  with  respect  to  priority   only,   any  necessary
          recordation and/or filing has been accomplished (including therein any
          necessary  descriptions  of  after-acquired  real  property  and  real
          property upon which  after-acquired  fixtures are affixed) will,  upon
          such  acquisition,  become subject to the first mortgage lien thereof,
          subject,  however,  to  Excepted  Encumbrances  and to liens,  if any,
          existing or placed thereon at the time of the  acquisition  thereof by
          the Company and,  with  respect to priority  only,  to liens,  if any,
          existing prior to the time of any necessary  recordation and/or filing
          by the Company; and

               (iv) The Company is the owner of the rights  conferred upon it by
          the leases  from the Navajo  Tribe  relating  to the site on which the
          Four  Corners  plant is located and while such counsel is not aware of

                                       15

          the assertion of any claim contesting the interest of the Navajo Tribe
          in the lands leased, such counsel shall not be required to express any
          opinion  with respect to the interest of the Navajo Tribe in the lands
          leased or with respect to the  enforceability  of such leases  against
          the Navajo Tribe.

In giving such opinion, Keleher & McLeod, P.A. may rely solely upon certificates
of the Company as to any factual matters upon which any such opinions are based.

          (f) The Underwriters or the  Representatives  shall have received from
     counsel for the  Underwriters  such opinion or opinions,  dated the Closing
     Date, with respect to the incorporation of the Company, the validity of the
     Purchased  Bonds, the Registration  Statements,  the Prospectus,  and other
     related  matters as may reasonably be required,  and the Company shall have
     furnished to such counsel such documents as they request for the purpose of
     enabling them to pass upon such matters.  In rendering  such opinion,  such
     counsel  may rely as to the  incorporation  of the  Company  and all  other
     matters  governed  by the laws of the States of Arizona and New Mexico upon
     the opinions of Snell & Wilmer L.L.P. and Keleher & McLeod,  P.A., referred
     to above.

          (g) The  Underwriters  or the  Representatives  shall have  received a
     certificate  of  the  President  or  any  Vice  President  and a  principal
     financial or accounting officer of the Company,  dated the Closing Date, in
     which  such  officers,  to the best of  their  knowledge  after  reasonable
     investigation,  shall state that the  representations and warranties of the
     Company  in this  Agreement  are true and  correct,  that the  Company  has
     complied with all agreements and satisfied all conditions on its part to be
     performed or satisfied at or prior to the Closing Date,  that no stop order
     suspending the  effectiveness  of the First  Registration  Statement or the
     Second  Registration  Statement has been issued and no proceedings for that
     purpose have been instituted or are  contemplated  by the  Commission,  and
     that, subsequent to the date of the most recent financial statements in the
     Prospectus,  there has been no  material  adverse  change in the  financial
     position  or results of  operations  of the  Company  and its  subsidiaries
     except as set forth or  contemplated  in the  Prospectus or as described in
     such certificate.

          (h) The  Underwriters  or the  Representatives  shall have  received a
     letter of DELOITTE & TOUCHE LLP,  dated the Closing  Date,  which meets the
     requirements  of subsection (a) of this Section,  except that the specified
     date referred to in such  subsection will be a date not more than five days
     prior to the Closing Date for the purposes of this subsection.

                                       16

     The Company will furnish the Underwriters or the Representatives  with such
conformed copies of such opinions,  certificates,  letters, and documents as may
be reasonably requested.

     6.  INDEMNIFICATION.  (a) The Company will indemnify and hold harmless each
Underwriter and each person,  if any, who controls such  Underwriter  within the
meaning of the Act against any losses, claims, damages or liabilities,  joint or
several,  to which  such  Underwriter  or such  controlling  person  may  become
subject, under the Act or otherwise, insofar as such losses, claims, damages, or
liabilities  (or actions in respect  thereof) arise out of or are based upon any
untrue  statement or alleged untrue  statement of any material fact contained in
any part of the Registration  Statements  relating to the Bonds,  when such part
became  effective,   any  preliminary   prospectus  or  preliminary   prospectus
supplement, the Prospectus, or any amendment or supplement thereto, or arise out
of or are  based  upon the  omission  or  alleged  omission  to state  therein a
material fact required to be stated  therein or necessary to make the statements
therein  not  misleading;  and will  reimburse  each  Underwriter  and each such
controlling person for any legal or other expenses  reasonably  incurred by such
Underwriter  or such  controlling  person in connection  with  investigating  or
defending any such loss, claim, damage, liability, or action; provided, however,
that the Company will not be liable in any such case to the extent that any such
loss,  claim,  damage,  or  liability  arises  out of or is based upon an untrue
statement or alleged  untrue  statement or omission or alleged  omission made in
any  of  such  documents  in  reliance  upon  and  in  conformity  with  written
information  furnished to the Company by any  Underwriter  specifically  for use
therein. This indemnity agreement will be in addition to any liability which the
Company may otherwise have.

          (b) Each  Underwriter  will severally  indemnify and hold harmless the
     Company,  each of its  directors,  each of its officers who have signed the
     Registration Statements,  and each person, if any, who controls the Company
     within the  meaning of the Act,  against any losses,  claims,  damages,  or
     liabilities  to  which  the  Company  or any  such  director,  officer,  or
     controlling person may become subject, under the Act or otherwise,  insofar
     as such losses,  claims,  damages,  or  liabilities  (or actions in respect
     thereof)  arise out of or are based  upon any untrue  statement  or alleged
     untrue  statement  of  any  material  fact  contained  in any  part  of the
     Registration  Statements  relating  to the  Bonds,  when such  part  became
     effective, any preliminary prospectus or preliminary prospectus supplement,
     the Prospectus,  or any amendment or supplement thereto, or arise out of or
     are based upon the  omission  or the alleged  omission  to state  therein a
     material  fact  required  to be stated  therein  or  necessary  to make the
     statements therein not misleading,  in each case to the extent, but only to
     the extent,  that such untrue  statement  or alleged  untrue  statement  or
     omission or alleged  omission was made in reliance  upon and in  conformity

                                       17

     with  written  information  furnished  to the  Company by such  Underwriter
     specifically  for use  therein;  and  will  reimburse  any  legal  or other
     expenses reasonably incurred by the Company or any such director,  officer,
     or controlling  person in connection  with  investigating  or defending any
     such loss, claim,  damage,  liability,  or action. This indemnity agreement
     will be in addition to any liability  which such  Underwriter may otherwise
     have.

          (c) Promptly after receipt by an indemnified  party under this Section
     of notice of the commencement of any action,  such indemnified  party will,
     if a claim in respect thereof is to be made against the indemnifying  party
     under this  Section,  notify  the  indemnifying  party of the  commencement
     thereof;  but the  omission  so to notify the  indemnifying  party will not
     relieve it from any  liability  that it may have to any  indemnified  party
     otherwise  than  under  this  Section.  In case any such  action is brought
     against any indemnified  party, and it notifies the  indemnifying  party of
     the  commencement  thereof,  the  indemnifying  party will be  entitled  to
     participate  therein and, to the extent that it may wish,  jointly with any
     other indemnifying party similarly notified, to assume the defense thereof,
     with counsel satisfactory to such indemnified party (who shall not, without
     the  consent of the  indemnified  party,  be  counsel  to the  indemnifying
     party),  and after notice from the  indemnifying  party to such indemnified
     party of its election so to assume the defense  thereof,  the  indemnifying
     party will not be liable to such  indemnified  party under this Section for
     any legal or other expenses subsequently incurred by such indemnified party
     in  connection  with the defense  thereof  other than  reasonable  costs of
     investigation. An indemnifying party shall not be liable for any settlement
     of a claim or action effected without its written consent,  which shall not
     be unreasonably withheld.

          (d) If the indemnification provided for in this Section is unavailable
     or insufficient to hold harmless an indemnified  party for any loss, claim,
     damage, liability, or action described in subsection (a) or (b) above, then
     each  indemnifying  party shall contribute to the amount paid or payable by
     such  indemnified  party as a result  of the  losses,  claims,  damages  or
     liabilities  referred to in  subsection  (a) or (b) above on the  following
     basis: (l) if such loss, claim, damage,  liability,  or action arises under
     subsection  (a) above,  then (i) in such  proportion as is  appropriate  to
     reflect the relative  benefits  received by the Company on the one hand and
     the Underwriters on the other from the offering of the Bonds or (ii) if the

                                       18

     allocation provided by clause (i) above is not permitted by applicable law,
     in such  proportion  as is  appropriate  to reflect  not only the  relative
     benefits referred to in clause (i) above but also the relative fault of the
     Company  on the one hand and the  Underwriters  on the other in  connection
     with the  statements or omissions  which  resulted in such losses,  claims,
     damages  or   liabilities   as  well  as  any  other   relevant   equitable
     considerations;  and (2) if such loss, claim, damage,  liability, or action
     arises  under  subsection  (b)  above,   then  in  such  proportion  as  is
     appropriate  to reflect the  relative  fault of the Company on the one hand
     and the  Underwriters  on the other in  connection  with the  statements or
     omissions which resulted in such losses,  claims, damages or liabilities as
     well as any other relevant  equitable  considerations.  For the purposes of
     clause (1) above, the relative  benefits received by the Company on the one
     hand and the  Underwriters  on the other  shall be deemed to be in the same
     proportion  as the total net proceeds from the offering  (before  deducting
     expenses) received by the Company bear to the total underwriting  discounts
     and commissions  received by the Underwriters.  For the purposes of clauses
     (1) and (2) above,  the relative fault shall be determined by reference to,
     among other  things,  whether the untrue or alleged  untrue  statement of a
     material fact or the omission or alleged  omission to state a material fact
     relates to information  supplied by the Company or the Underwriters and the
     parties' relative intent, knowledge,  access to information and opportunity
     to correct or prevent such untrue statement or omission. The amount paid by
     an  indemnified  party  as a  result  of the  losses,  claims,  damages  or
     liabilities  referred to in the first sentence of this subsection (d) shall
     be deemed to include  any legal or other  expenses  reasonably  incurred by
     such  indemnified  party in connection with  investigating or defending any
     action or claim  which is the  subject of this  subsection  (d).  No person
     guilty of fraudulent misrepresentation (within the meaning of Section 11(f)
     of the Act) shall be entitled to  contribution  from any person who was not
     guilty of such fraudulent misrepresentation.  The Underwriters' obligations
     in this  subsection  (d) to  contribute  are several in proportion to their
     respective underwriting obligations and not joint.

     7. DEFAULT OF UNDERWRITERS.  If any Underwriter or Underwriters  default in
their obligations to purchase Purchased Bonds pursuant to this Agreement and the
Terms Agreement and the principal amount of Purchased Bonds that such defaulting
Underwriter or  Underwriters  agreed but failed to purchase is ten percent (10%)
or less of the principal amount of Purchased Bonds to which such Terms Agreement
relates,   the  Underwriters  or  the   Representatives  may  make  arrangements
satisfactory  to the Company for the purchase of such  Purchased  Bonds by other
persons, including any of the Underwriters, but if no such arrangements are made
by the Closing Date the nondefaulting Underwriters shall be obligated severally,

                                       19

in proportion  to their  respective  commitments  hereunder and under such Terms
Agreement,  to purchase the Purchased Bonds that such defaulting  Underwriter or
Underwriters  agreed but failed to purchase.  If any Underwriter or Underwriters
so default and the aggregate principal amount of Purchased Bonds with respect to
which such default or defaults occur is more than the above-described amount and
arrangements  satisfactory to the remaining Underwriters and the Company for the
purchase of such Purchased Bonds by other persons are not made within thirty-six
hours after such default,  the Terms Agreement will terminate  without liability
on the part of any non-defaulting Underwriter or the Company, except as provided
in Section 8. As used in this  Agreement,  the term  "Underwriter"  includes any
person  substituted for an Underwriter  under this Section.  Nothing herein will
relieve a defaulting Underwriter from liability for its default.

     8. SURVIVAL OF CERTAIN  REPRESENTATIONS  AND  OBLIGATIONS.  The  respective
indemnities,  agreements,  representations,  warranties, and other statements of
the Company or its officers and of the several Underwriters set forth in or made
pursuant to this  Agreement  will remain in full force and effect  regardless of
any investigation,  or statement as to the results thereof, made by or on behalf
of any  Underwriter  or the Company or any of its  officers or  directors or any
controlling  person,  and will survive delivery of and payment for the Purchased
Bonds. If any Terms Agreement is terminated pursuant to Section 7, or if for any
reason a  purchase  pursuant  to any Terms  Agreement  is not  consummated,  the
Company shall remain responsible for the expenses to be paid or reimbursed by it
pursuant  to Section 4 and the  respective  obligations  of the  Company and the
Underwriters pursuant to Section 6 shall remain in effect.

     9.  NOTICES.  All  communications  hereunder  relating  to any  offering of
Purchased  Bonds will be in writing,  and, if sent to the  Underwriters,  may be
mailed, delivered, or telecopied and confirmed to the Representative first named
in the Terms Agreement  relating to such Purchased Bonds or the  Underwriters at
their  addresses  furnished  to the  Company  in  writing  for  the  purpose  of
communications; provided, however, that any notice to an Underwriter pursuant to
Section 6 will be mailed,  delivered,  or telecopied  and confirmed to each such
Underwriter  at its own  address.  All  communications  hereunder to the Company
shall be  mailed  to the  Company,  Attention:  Treasurer,  at P.O.  Box  53999,
Phoenix,  Arizona 85072-3999,  or delivered,  or telecopied and confirmed to the
Company at 400 North Fifth Street, Phoenix, Arizona 85004.

     10. SUCCESSORS.  This Agreement will inure to the benefit of and be binding
upon the parties hereto and such  Underwriters as are named in Terms  Agreements
and their  respective  successors and the officers and directors and controlling

                                       20

persons  referred  to in Section 6, and no other  person  will have any right or
obligation hereunder.

     11.  REPRESENTATION OF UNDERWRITERS.  The Representatives,  if any, may act
for the several  Underwriters  in connection  with any offering to which a Terms
Agreement  may  relate,  and any  action  under  this  Agreement  or such  Terms
Agreement taken by the Representatives jointly or the Representative first named
in  such  Terms  Agreement  in  such  capacity  will  be  binding  upon  all the
Underwriters of Purchased Bonds to which such Terms Agreement relates.

     12. EXECUTION IN COUNTERPART. This Agreement and any Terms Agreement may be
executed  in one or more  counterparts,  each of which  shall be deemed to be an
original,  but all such  respective  counterparts  shall  together  constitute a
single instrument.

                                       21

     If the foregoing is in accordance with your understanding of our agreement,
kindly sign and return to us the enclosed  duplicate  hereof,  whereupon it will
become a binding agreement  between the Company and the several  Underwriters in
accordance with its terms.

                                          Very truly yours,

                                          ARIZONA PUBLIC SERVICE COMPANY


                                          By
                                             -----------------------------------
                                             Treasurer


The foregoing  Underwriting Agreement
is hereby confirmed and accepted as
of the date first above written.


By
   -----------------------------------