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                                                                     EXHIBIT 3.1

                                     BYLAWS
                                       OF
                         ARIZONA PUBLIC SERVICE COMPANY
                        (AMENDED AS OF JANUARY 21, 2004)


                            I. REFERENCES; SENIORITY

         1.01. REFERENCES. Any reference herein made to law will be deemed to
refer to the law of the State of Arizona, including any applicable provision or
provisions of Chapters 1-17 and Chapter 23 of Title 10, Arizona Revised Statutes
(or its successor), as at any given time in effect. Any reference herein made to
the Articles will be deemed to refer to the applicable provision or provisions
of the Articles of Incorporation of the Company, and all amendments thereto, as
at any given time on file with the Arizona Corporation Commission (this
reference to that Commission being intended to include any successor to the
incorporating and related functions being performed by that Commission at the
date of the initial adoption of these Bylaws).

         1.02. SENIORITY. Except as indicated in Part X of these Bylaws, the law
and the Articles (in that order of precedence) will in all respects be
considered senior and superior to these Bylaws, with any inconsistency to be
resolved in favor of the law and the Articles (in that order of precedence), and
with these Bylaws to be deemed automatically amended from time to time to
eliminate any such inconsistency which may then exist.

         1.03. SHAREHOLDERS OF RECORD. Except as otherwise required by law and
subject to any procedure established by the Company pursuant to Arizona Revised
Statutes Section 10-723 (or any comparable successor provision), the word
"shareholder" as used herein shall mean one who is a holder of record of shares
in the Company.

                            II. SHAREHOLDERS MEETINGS

         2.01. ANNUAL MEETINGS. An annual meeting of shareholders shall be held
for the election of directors at such date, time and place, either within or
without the State of Arizona, as may be designated by resolution of the Board of
Directors from time to time. Any other proper business may be transacted at the
annual meeting. A special meeting may be called and held in lieu of an annual
meeting pursuant to the provisions of Section 2.02 below, and the same
proceedings (including the election of directors) may be conducted thereat as at
a regular meeting. Any director elected at any annual meeting, or special
meeting in lieu of an annual meeting, will continue in office until the election
of his or her successor, subject to his or her (a) earlier resignation pursuant
to Section 6.01 below, (b) removal pursuant to Section 3.12 below, or (c) death
or disqualification.

         2.02. SPECIAL MEETINGS. Except as otherwise required by law, special
meetings of the shareholders may be held whenever and wherever called by the
Chairman of the Board, the President, or a majority of the Board of Directors. A
special meeting of shareholders shall also be called by the President or the
Secretary at the written request of the holder or holders of not less than
seventy-five percent (75%) of all outstanding votes entitled to be cast on any
matter to

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be voted on at the meeting. Any such written request by shareholders shall state
the purpose or purposes of the proposed meeting, and business to be transacted
at any such meeting shall be confined to the purposes stated in the notice
thereof and to such additional matters as the chairman of the meeting may rule
to be germane to such purposes.

         2.03. NOTICE. Notice of any meeting of the shareholders will be given
as provided by law to each shareholder entitled to vote at such meeting and, if
required by law, to each other shareholder of the Company. Any such notice may
be waived as provided by law.

         2.04. RIGHT TO VOTE. For each meeting of the shareholders, the Board of
Directors will fix in advance a record date as contemplated by law, and the
shares of stock and the shareholders "entitled to vote" (as that or any similar
term is herein used) at any meeting of the shareholders will be determined as of
the applicable record date. If no record date is so fixed by the Board of
Directors, the record date for determination of shareholders shall be as
provided by law. The Secretary (or in his or her absence an Assistant Secretary)
will see to the making and production of any record of shareholders entitled to
vote or otherwise entitled to notice of shareholders meetings, in either case
which is required by law. Any voting entitlement may be exercised through proxy,
or in such other manner as specifically provided by law, in accordance with the
applicable law. In the event of contest, the burden of proving the validity of
any undated or irrevocable proxy will rest with the person seeking to exercise
the same. A telegram, cablegram, or facsimile appearing to have been transmitted
by a shareholder (or by his or her duly authorized attorney-in-fact) or other
means of voting by telephone or electronic transmission may be accepted as a
sufficiently written and executed proxy if otherwise permitted by law.

         2.05. RIGHT TO ATTEND. Except only to the extent of persons designated
by the Board of Directors or the Chairman of the meeting to assist in the
conduct of the meeting (as referred to in Sections 2.07 and 2.08 below) and
except as otherwise permitted by the Board or such Chairman, the persons
entitled to attend any meeting of shareholders may be confined to (i)
shareholders entitled to vote thereat and other shareholders entitled to notice
of the meeting and (ii) the persons upon whom proxies valid for purposes of the
meeting have been conferred or their duly appointed substitutes (if the related
proxies confer a power of substitution); provided, however, that the Board of
Directors or the Chairman of the meeting may establish rules limiting the number
of persons referred to in clause (ii) as being entitled to attend on behalf of
any shareholder so as to preclude such an excessively large representation of
such shareholder at the meeting as, in the judgment of the Board or such
Chairman, would be unfair to other shareholders represented at the meeting or be
unduly disruptive of the orderly conduct of business at such meeting (whether
such representation would result from fragmentation of the aggregate number of
shares held by such shareholder for the purpose of conferring proxies, from the
naming of an excessively large proxy delegation by such shareholder or from
employment of any other device). A person otherwise entitled to attend any such
meeting will cease to be so entitled if, in the judgment of the Chairman of the
meeting, such person engages thereat in disorderly conduct impeding the proper
conduct of the meeting in the interests of all shareholders as a group.

         2.06. QUORUM. Except as otherwise provided by law, the Articles or
these Bylaws, at each meeting of shareholders the presence in person or by proxy
of the holders of a majority in

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voting power of the outstanding shares of stock entitled to vote at the meeting
shall be necessary and sufficient to constitute a quorum.

         2.07. ELECTION INSPECTORS. The Board of Directors, in advance of any
shareholders meeting may appoint an election inspector or inspectors to act at
such meeting (and any adjournment thereof). If an election inspector or
inspectors are not so appointed, the Chairman of the meeting may or, upon the
request of any person entitled to vote at the meeting will, make such
appointment. If any person appointed as an inspector fails to appear or to act,
a substitute may be appointed by the Chairman of the meeting. If appointed, the
election inspector or inspectors (acting through a majority of them if there be
more than one) will determine the number of shares outstanding, the
authenticity, validity and effect of proxies, the credentials of persons
purporting to be shareholders or persons named or referred to in proxies, and
the number of shares represented at the meeting in person and by proxy; they
will receive and count votes, ballots and consents and announce the results
thereof; they will hear and determine all challenges and questions pertaining to
proxies and voting; and, in general, they will perform such acts as may be
proper to conduct elections and voting with complete fairness to all
shareholders. No such election inspector need be a shareholder of the Company.

         2.08. ORGANIZATION AND CONDUCT OF MEETINGS. Each shareholders meeting
will be called to order and thereafter chaired by the Chairman of the Board if
there then is one; or, if not, or if the Chairman of the Board is absent or so
requests, then by the President; or if both the Chairman of the Board and the
President are unavailable, then by such other officer of the Company or such
shareholder as may be appointed by the Board of Directors. The Secretary (or in
his or her absence an Assistant Secretary) of the Company will act as secretary
of each shareholders meeting; if neither the Secretary nor an Assistant
Secretary is in attendance, the Chairman of the meeting may appoint any person
(whether a shareholder or not) to act as secretary thereat. After calling a
meeting to order, the Chairman thereof may require the registration of all
shareholders intending to vote in person, and the filing of all proxies, with
the election inspector or inspectors, if one or more have been appointed (or, if
not, with the secretary of the meeting). After the announced time for such
filing of proxies has ended, no further proxies or changes, substitutions or
revocations of proxies will be accepted. If directors are to be elected, a
tabulation of the proxies so filed will, if any person entitled to vote in such
election so requests, be announced at the meeting (or adjournment thereof) prior
to the closing of the election polls.

         Absent a showing of bad faith on his or her part, the Chairman of a
meeting will, among other things, have absolute authority to determine the order
of business to be conducted at such meeting and to establish rules for, and
appoint personnel to assist in, preserving the orderly conduct of the business
of the meeting (including any informal, or question and answer, portions
thereof). Rules, regulations or procedures regarding the conduct of the business
of a meeting, whether adopted by the Board of Directors or prescribed by the
Chairman of the meeting, may include, without limitation, the following: (i) the
establishment of an agenda or order of business for the meeting; (ii) rules and
procedures for maintaining order at the meeting and the safety of those present;
(iii) limitations on attendance at or participation in the meeting to
shareholders of record of the Company, their duly authorized and constituted
proxies (subject to Section 2.05) or such other persons as the Chairman of the
meeting shall determine; (iv) restrictions on entry to the meeting after the
time fixed for the commencement thereof; and (v) limitations on the time

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allotted to questions or comments by participants. Unless and to the extent
determined by the Board of Directors or the Chairman of the meeting, meetings of
shareholders shall not be required to be held in accordance with the rules of
parliamentary procedure. Any informational or other informal session of
shareholders conducted under the auspices of the Company after the conclusion of
or otherwise in conjunction with any formal business meeting of the shareholders
will be chaired by the same person who chairs the formal meeting, and the
foregoing authority on his or her part will extend to the conduct of such
informal session.

         2.09. VOTING. The number of shares voted on any matter submitted to the
shareholders which is required to constitute their action thereon or approval
thereof will be determined in accordance with applicable law, the Articles, and
these Bylaws, if applicable. No ballot or change of vote will be accepted after
the polls have been declared closed following the ending of the announced time
for voting.

         2.10. SHAREHOLDER APPROVAL OR RATIFICATION. The Board of Directors may
submit any contract or act for approval or ratification at any duly constituted
meeting of the shareholders, the notice of which either includes mention of the
proposed submittal or is waived as provided in Section 2.03 above. Except as
otherwise required by law (e.g., Arizona Revised Statutes Section 10-863), if
any contract or act so submitted is approved or ratified by a majority of the
votes cast thereon at such meeting, the same will be valid and as binding upon
the Company and all of its shareholders as it would be if approved and ratified
by each and every shareholder of the Company.

         2.11. ADJOURNMENTS. Any meeting of shareholders, annual or special, may
adjourn from time to time to reconvene at the same or some other place, and
notice need not be given of any such adjourned meeting if the time and place
thereof are announced at the meeting at which the adjournment is taken. At the
adjourned meeting the Company may transact any business that might have been
transacted at the original meeting. If the adjournment is for more than one
hundred and twenty days, or if after the adjournment a new record date is fixed
for the adjourned meeting, notice of the adjourned meeting shall be given to
each shareholder of record entitled to vote at the meeting.

         2.12. SHAREHOLDER ACTION BY WRITTEN CONSENT. Any action required or
permitted to be taken at a meeting of the shareholders may be taken without a
meeting if one (1) or more consents in writing, setting forth the action so
taken, shall be signed by all of the shareholders entitled to vote with respect
to the subject matter thereof. The consents shall be delivered to the Company
for inclusion in the minutes or filing with the Company's records. Action taken
by consent is effective when the last shareholder signs the consent, unless the
consent specifies a different effective date, except that if, by law, the action
to be taken requires that notice be given to shareholders who are not entitled
to vote on the matter, the effective date shall not be prior to ten (10) days
after the Company shall give such shareholders written notice of the proposed
action, which notice shall contain or be accompanied by the same material that
would have been required if a formal meeting had been called to consider the
action. A consent signed under this section has the effect of a meeting vote and
may be described as such in any document.

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                             III. BOARD OF DIRECTORS

         3.01. MEMBERSHIP AND QUALIFICATION. The Board of Directors will have
the exclusive power to increase or decrease its size within the limits fixed in
the Articles (Art. Fifth). Any vacancy occurring in the Board, whether by reason
of death, resignation, disqualification or otherwise, may be filled by the
directors as contemplated by law and as provided in the Articles (Art. Fifth).
Any such increase in the size of the Board, and the filling of any vacancy
created thereby, will require action by a majority of the whole membership of
the Board as comprised immediately before such increase. A person will not
qualify for election or appointment as a director, whether initially or on
re-election and whether by the shareholders at their annual meeting or by the
Board of Directors as contemplated in this Section 3.01, if such person's 72nd
birthday occurs on or has occurred before the date of such election, appointment
or re-election. A person who has been a full-time employee of the Company within
twelve months prior to the date of any election will not qualify for election as
a director on that date unless he or she then remains a full-time employee of
the Company or unless the Board of Directors specifically authorizes the
election of such person (but it is not intended that any such authorization will
extend a person's service on the Board beyond the age limitation set out in the
preceding sentence). A person who has qualified by age or employment status for
his or her most recent election as a director may serve throughout the term for
which such person was elected, notwithstanding the occurrence of his or her 72nd
birthday or cessation of full-time employment by the Company between the date of
such election and the end of such term, subject, however, to his or her
otherwise remaining qualified for such office.

         3.02. REGULAR MEETINGS. A regular annual meeting of the directors is to
be held as soon as practicable after the adjournment of each annual shareholders
meeting either at the place of the shareholders meeting or at such other place
as the directors elected at the shareholders meeting may have been informed of
at or before the time of their election. Regular meetings, other than the annual
ones, may be held at such intervals at such places and at such times as the
Board of Directors may provide.

         3.03. SPECIAL MEETINGS. Special meetings of the Board of Directors may
be held whenever and wherever called for by the Chairman of the Board, the
President or the number of directors which would be required to constitute a
quorum.

         3.04. NOTICE. No notice need be given of regular meetings of the Board
of Directors. Notice of the time and place (but not necessarily the purpose or
all of the purposes) of any special meeting will be given to each director in
person or by telephone, or via mail, telegram, facsimile, or other electronic
transmission addressed in the manner appearing on the Company's records. Notice
to any director of any such special meeting will be deemed given sufficiently in
advance when (i) if given by mail, the same is deposited in the United States
mail at least four days before the meeting date, with postage thereon prepaid,
(ii) if given by telegram, the same is delivered to the telegraph office for
fast transmittal at least 48 hours prior to the convening of the meeting, (iii)
if given by facsimile or other electronic transmission, the same is received by
the director or an adult member of his or her office staff or household, at
least 24 hours prior to the convening of the meeting, or (iv) if personally
delivered or given by telephone, the same is handed, or the substance thereof is
communicated over the telephone to the director or to an adult member of his or
her office staff or household, at least 24 hours prior to the convening of

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the meeting. Any such notice may be waived as provided by law. No call or notice
of a meeting of directors will be necessary if each of them waives the same in
writing or by attendance. Any meeting, once properly called and noticed (or as
to which call and notice have been waived as aforesaid) and at which a quorum is
formed, may be adjourned to another time and place by a majority of those in
attendance.

         3.05. QUORUM; VOTING. A quorum for the transaction of business at any
meeting or adjourned meeting of the directors will consist of a majority of
those then in office. Any matter submitted to a meeting of the directors will be
resolved by a majority of the votes cast thereon, except as otherwise required
by these Bylaws (Section 3.01 above and Section 3.06 below), by law or by any
applicable Article. However, in case of an equality of votes, the Chairman of
the meeting will have a second or deciding vote. Where action by a majority of
the whole membership is required, such requirement will be deemed to relate to a
majority of the directors in office at the time the action is taken. In
computing any such majority, whether for purposes of determining the presence of
a quorum or the adequacy of the vote on any proposed action, any unfilled
vacancies at the time existing in the membership of the Board will be excluded
from the computation.

         3.06. EXECUTIVE COMMITTEE. The Board of Directors may, by resolution
adopted by a majority of the whole Board, name three or more of its members as
an Executive Committee. Such Executive Committee will have and may exercise the
powers of the Board of Directors in the management of the business and affairs
of the Company while the Board is not in session, except only as precluded by
law or where action other than by a majority of the votes cast is required by
these Bylaws, or the law (all as referred to in Section 3.05 above), and subject
to such limitations as may be included in any applicable resolution passed by a
majority of the whole membership of the Board. A majority of those named to the
Executive Committee will constitute a quorum.

         3.07. OTHER COMMITTEES. The Board of Directors may designate one or
more additional committees, each committee to consist of one or more of the
directors of the Company. The Board of Directors may designate one or more
directors as alternate members of any committee, who may replace any absent or
disqualified member at any meeting of the committee. Any such committee, to the
extent permitted by law and to the extent provided in the resolution of the
Board of Directors, shall have and may exercise all the powers and authority of
the Board of Directors in the management of the business and affairs of the
Company, and may authorize the seal of the Company to be affixed to all papers
that may require it.

         3.08. COMMITTEE FUNCTIONING. Notice requirements (and related waiver
provisions) for meetings of the Executive Committee and other committees of the
Board will be the same as those set forth in Section 3.04 above for meetings of
the Board of Directors. Except as provided in the next two succeeding sentences,
a majority of those named to the Executive Committee or any other committee of
the Board will constitute a quorum at any meeting thereof (with the effect of
departure of committee members from a meeting and the computation of a majority
of committee members to be in accordance with the applicable policies of Section
3.05 above), and any matter submitted to a meeting of any such committee will be
resolved by a majority of the votes cast thereon. No distinction will be made
among ex-officio or other members of any such committee for quorum, voting or
other purposes, except that the membership of any committee

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(including the Executive Committee), in performing any function vested in it as
herein contemplated, may be deemed to exclude any officer or employee of the
Company, in either case, or other person, having a direct or indirect personal
interest in any proposed exercise of such function, whose exclusion for that
purpose is deemed appropriate by a majority of the other members of such
committee proposing to perform such function. All committees are to keep regular
minutes of the transactions of their meetings.

         3.09. ACTION BY TELEPHONE OR CONSENT. Any meeting of the Board or any
committee thereof may be held by conference telephone or similar communications
equipment as permitted by law in which case any required notice of such meeting
may generally describe the arrangements (rather than the place) for the holding
thereof, and all other provisions herein contained or referred to will apply to
such meeting as though it were physically held at a single place. Action may
also be taken by the Board or any committee thereof without a meeting if the
members thereof consent in writing thereto as contemplated by law.

         3.10. PRESUMPTION OF ASSENT. A director of the Company who is present
at a meeting of the Board of Directors, or of any committee when corporate
action is taken is deemed to have assented to the action taken unless either (i)
the director objects at the beginning of the meeting or promptly on the
director's arrival to holding it or transacting business at the meeting; (ii)
the director's dissent or abstention from the action taken is entered in the
minutes of the meeting; or (iii) the director delivers written notice of the
director's dissent or abstention to the presiding officer of the meeting before
its adjournment or to the Company before 5:00 P.M. on the next business day
after the meeting. The right of dissent or abstention is not available to a
director who votes in favor of the action taken.

         3.11. COMPENSATION. By resolution of the Board, the directors may be
paid their expenses, if any, of attendance at each meeting of the Board of
Directors, or of any committee, and may be paid a fixed sum for attendance at
each such meeting and/or a stated salary as a director or committee member. No
such payment will preclude any director from serving the Company in any other
capacity and receiving compensation therefor.

         3.12. REMOVAL. Any director or the entire Board of Directors may be
removed with or without cause, only at a special meeting of shareholders called
for that purpose, by the affirmative vote of sixty-six and two-thirds percent
(66 2/3%) of the issued and outstanding shares of stock then entitled to vote on
the election of directors, except that if less than the entire Board of
Directors is to be removed, no one of the directors may be removed if the votes
cast against the director's removal would be sufficient to elect the director if
then cumulatively voted at an election for the class of directors of which the
director is a part.

                             IV. OFFICERS - GENERAL

         4.01. ELECTIONS AND APPOINTMENTS. The directors may elect or appoint
one or more of the officers of the Company contemplated in Part V below. Any
such election or appointment will regularly take place at the annual meeting of
the directors, but elections of officers may be held at any other meeting of the
Board. A person elected or appointed to any office will continue to hold that
office until the election or appointment of his or her successor, subject to
action earlier taken pursuant to Section 4.04 or 6.01 below. Any person may hold
more than one office.

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         4.02. ADDITIONAL APPOINTMENTS. In addition to the officers contemplated
in Part V below, the Board of Directors may create other corporate positions,
and appoint persons thereto, with such authority to perform such duties as may
be prescribed from time to time by the Board of Directors, by the President or
by the superior officer of any person so appointed. Notwithstanding such
additional appointments, only those persons whose offices are described in Part
V are to be considered an officer of the Company unless the resolution or other
Board action appointing such person expressly states that such person is to be
considered an officer of the Company. Each of such persons (in the order
designated by the Board or the superior officer of such person) will be vested
with all of the powers and charged with all of the duties of his or her superior
officer in the event of such superior officer's absence or disability.

         4.03. BONDS AND OTHER REQUIREMENTS. The Board of Directors may require
any officer or other appointee to give bond to the Company (with sufficient
surety, and conditioned upon the faithful performance of the duties of his or
her office or position) and to comply with such other conditions as may from
time to time be required of him or her by the Board.

         4.04. REMOVAL OR DELEGATION. Provided that a majority of the whole
membership thereof concurs therein, the Board of Directors may remove any
officer of the Company as provided by law and declare his or her office or
offices vacant or abolished or, in the case of the absence or disability of any
officer or for any other reason considered sufficient, may temporarily delegate
his or her powers and duties to any other officer or to any director. Similar
action may be taken by the Board of Directors in regard to appointees designated
pursuant to Section 4.02 above.

         4.05. SALARIES. Officer salaries may from time to time be fixed by the
Board of Directors or (except as to his or her own) be left to the discretion of
the Chief Executive Officer or the President. No officer will be prevented from
receiving a salary by reason of the fact that he or she is also a director of
the Company.

                   V. SPECIFIC OFFICERS, FUNCTIONS AND POWERS

         5.01. CHAIRMAN OF THE BOARD. The Board of Directors may elect a
Chairman to serve as a general executive officer of the Company and, if
specifically designated as such by the Board, as the Chief Executive Officer of
the Company. If elected, the Chairman will preside at all meetings of the
directors and be vested with such other powers and duties as the Board may from
time to time delegate to him or her.

         5.02. CHIEF EXECUTIVE OFFICER. Subject to the control of the Board of
Directors exercised as hereinafter provided, the Chief Executive Officer of the
Company will supervise its business and affairs and the performance of their
respective duties by all other officers, by appointees designated pursuant to
Section 4.02 above, and by such additional appointees to such additional
positions (corporate, divisional or otherwise) as the Chief Executive Officer
may designate, with authority on his or her part to delegate the foregoing duty
of supervision to such extent and to such person or persons as may be determined
by the Chief Executive Officer. Except as otherwise indicated from time to time
by resolution of the Board of Directors, its management of the business and
affairs of the Company will be implemented through the office of the Chief
Executive Officer.

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         5.03. PRESIDENT AND VICE PRESIDENTS. Unless specified to the contrary
by resolution of the Board of Directors, the President will be the Chief
Executive Officer of the Company. In addition to the supervisory functions above
set forth on the part of the Chief Executive Officer or in lieu thereof if a
contrary specification is made by the Board relative to the Chief Executive
Officer, the President will be vested with such powers and duties as the Board
may from time to time designate. Vice Presidents may be elected by the Board of
Directors to perform such duties as may be designated by the Board or be
assigned or delegated to them by their respective superior officers. The Board
may identify (i) one or more Vice Presidents as "Executive" or "Senior" Vice
Presidents and (ii) the President or any Vice President as "General Manager" of
the Company and the title of any Vice President may include words indicative of
his or her particular area of responsibility and authority. Vice Presidents will
succeed to the responsibilities and authority of the President, in the event of
his or her absence or disability, in the order consistent with their respective
titles or regular duties or as specifically designated by the Board of
Directors.

         5.04. TREASURER AND SECRETARY. The Treasurer and Secretary each will
perform all such duties normally associated with his or her office (including,
in the case of the Secretary, the giving of notice and the preparation and
retention of minutes of corporate proceedings and the custody of corporate
records and the seal of the Company) as are not assigned to a Vice President of
the Company, along with such other duties as may be designated by the Board or
be assigned or delegated to them by their respective superior officers. The
Board may appoint one or more Assistant Treasurers or Assistant Secretaries,
each of whom (in the order designated by the Board or their respective superior
officers) will be vested with all of the powers and charged with all of the
duties of the Treasurer or the Secretary (as the case may be) in the event of
his or her absence or disability.

         5.05. SPECIFIC POWERS. Except as may otherwise be specifically provided
in a resolution of the Board of Directors, any of the officers referred to in
this Part V will be a proper officer to authenticate records of the Company and
to sign on behalf of the Company any deed, bill of sale, assignment, option,
mortgage, pledge, note, bond, debenture, evidence of indebtedness, application,
consent (to service of process or otherwise), agreement, indenture or other
instrument of importance to the Company. Any such officer may represent the
Company at any meeting of the shareholders or members of any corporation,
association, partnership, joint venture or other entity in which this Company
then has an interest, and may vote such interest in person or by proxy appointed
by him or her, provided that the Board of Directors may from time to time confer
the foregoing authority upon any other person or persons.

                         VI. RESIGNATIONS AND VACANCIES

         6.01. RESIGNATIONS. Any director, committee member or officer may
resign from his or her office at any time by written notice as specified in
accordance with Arizona Revised Statutes Sections 10-807 and 10-843. The
acceptance of a resignation will not be required to make it effective.

         6.02. VACANCIES. If the office of any director, committee member or
officer becomes vacant by reason of his or her death, resignation,
disqualification, removal or otherwise, the Board of Directors may choose a
successor to hold office for the unexpired term.

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                      VII. INDEMNIFICATION AND RATIFICATION

         7.01. INDEMNIFICATION. In order to induce qualified persons to serve
the Company (and any other corporation, joint venture, partnership, trust or
other enterprise at the request of the Company) as directors and officers, the
Company shall indemnify any and all of its directors and officers, or former
directors and officers to the fullest extent permitted by applicable law as it
presently exists or may hereafter be amended.

         7.02. RATIFICATION; SPECIAL COMMITTEE. Any transaction involving the
Company, any of its subsidiary corporations or any of its directors, officers,
employees or agents which at any time is questioned in any manner or context
(including a shareholders derivative suit), on the ground of lack of authority,
conflict of interest, misleading or omitted statement of fact or law,
nondisclosure, miscomputation, improper principles or practices of accounting,
inadequate records, defective or irregular execution or any similar ground, may
be investigated and/or ratified (before or after judgment), or an election may
be made not to institute or pursue a claim or legal proceedings on account
thereof or to accept or approve a negotiated settlement with respect thereto
(before or after the institution of legal proceedings), by the Board of
Directors or by a special committee thereof comprised of one or more
disinterested directors (that is, a director or directors who did not
participate in the questioned transaction with actual knowledge of the
questioned aspect or aspects thereof). Such a special committee may be validly
formed and fully empowered to act, in accordance with the purposes and duties
assigned thereto, by resolution or resolutions of the Board of Directors,
notwithstanding (i) the inclusion of Board members who are not disinterested as
aforesaid among those who form a quorum at the meeting or meetings at which one
or more members of such special committee are elected or appointed to the Board
or to such special committee or at which such committee is formed or empowered,
or their inclusion among the directors who vote upon or otherwise participate in
taking any of the foregoing actions, or (ii) the taking of any of such actions
by the disinterested members of the Board (or a majority of such members) whose
number is not sufficient to constitute a quorum or a majority of the membership
of the full Board. Any such special committee so comprised will, to the full
extent consistent with its purposes and duties as expressed in such resolution
or resolutions, have all of the authority and powers of the full Board and its
Executive Committee (the same as though it were the full Board and/or its
Executive Committee in carrying out such purposes and duties) and will function
in accordance with Section 3.08 above. No other provisions of these Bylaws which
may at any time appear to conflict with any provisions of this Section 7.02, and
no defect or irregularity in the formation, empowering or functioning of any
such special committee, will serve to impede, impair or bring into question any
action taken or purported to be taken by such committee or the validity of any
such action. Any ratification of a transaction pursuant to this Section 7.02
will have the same force and effect as if the transaction has been duly
authorized originally. Any such ratification, and any election made pursuant to
this Section 7.02 with respect to claims, legal proceedings or settlements, will
be binding upon the Company and its shareholders and will constitute a bar to
any claim or the execution of any judgment in respect of the transaction
involved in such ratification or election.

                                   VIII. SEAL

         8.01. FORM THEREOF. The seal of the Company will have inscribed thereon
the name of the Company, the state and year of its incorporation and the words
"SEAL".

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<PAGE>

                             IX. STOCK CERTIFICATES

         9.01. FORM THEREOF. Each certificate representing stock of the Company
will be in such form conforming to law as may from time to time be approved by
the Board of Directors, and will bear the manual facsimile signatures and seal
of the Company as required or permitted by law.

         9.02. OWNERSHIP. The Company will be entitled to treat the registered
owner of any share as the absolute owner thereof and accordingly, will not be
bound to recognize any beneficial, equitable or other claim to, or interest in,
such share on the part of any other person, whether or not it has notice
thereof, except as may expressly be provided by Chapter 8 of Title 47, Arizona
Revised Statutes (or its successor), as at the time in effect, or other
applicable law.

         9.03. TRANSFERS. Transfer of stock will be made on the books of the
Company only upon surrender of the certificate therefor, duly endorsed by an
appropriate person, with such assurance of the genuineness and effectiveness of
the endorsement as the Company may require, all as contemplated by Chapter 8 of
Title 47, Arizona Revised Statutes (or its successor), as at the time in effect,
and/or upon submission of any affidavit, other document or notice which the
Company considers necessary.

         9.04. LOST CERTIFICATES. In the event of the loss, theft or destruction
of any certificate representing capital stock of this Company, the Company may
issue (or, in the case of any such stock as to which a transfer agent and/or
registrar have been appointed, may direct such transfer agent and/or registrar
to countersign, register and issue) a replacement certificate in lieu of that
alleged to be lost, stolen or destroyed, and cause the same to be delivered to
the owner of the stock represented thereby, provided that the owner shall have
submitted such evidence showing the circumstances of the alleged loss, theft or
destruction, and his or her ownership of the certificate as the Company
considers satisfactory, together with any other factors which the Company
considers pertinent, and further provided that an indemnity agreement and/or
indemnity bond shall have been provided in form and amount satisfactory to the
Company and to its transfer agent and/or registrar, if applicable.

                               X. EMERGENCY BYLAWS

         10.01. EMERGENCY CONDITIONS. The emergency Bylaws provided in this Part
X will be effective in the event of an emergency as prescribed in Arizona
Revised Statutes Section 10-207.D. To the extent not inconsistent with the
provisions of this Part X, these Bylaws will remain in effect during such
emergency and upon its termination these emergency Bylaws will cease to be
operative.

         10.02. BOARD MEETINGS. During any such emergency, a meeting of the
Board of Directors or any of its committees may be called by any officer or
director of the Company. Notice of the time and place of the meeting will be
given by the person calling the same to those of the directors whom it may be
feasible to reach by any available means of communication. Such notice will be
given so much in advance of the meeting as circumstances permit in the judgment
of the person calling the same. At any Board or committee meeting held during
any such emergency, a quorum will consist of a majority of those who could
reasonably be expected

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<PAGE>

to attend the meeting if they were willing to do so, but in no event more than a
majority of those to whom notice of such meeting is required to have been given
as above provided.

         10.03. CERTAIN ACTIONS. The Board of Directors, either before or during
any such emergency, may provide and from time to time modify lines of succession
in the event that during such an emergency any or all officers, appointees,
employees or agents of the Company are for any reason rendered incapable of
discharging their duties. The Board, either before or during any such emergency,
may, effective in the emergency, change the head office or designate several
alternative head offices of the Company, or authorize the officers to do so.

         10.04. LIABILITY. No director, officer, appointee, employee or agent
acting in accordance with these emergency Bylaws will be liable except for
willful misconduct.

         10.05. MODIFICATIONS. These emergency Bylaws will be subject to repeal
or change by further action of the Board of Directors, but no such repeal or
change will modify the provisions of Section 10.04 with respect to action taken
prior to the time of such repeal or change. Any amendment of these emergency
Bylaws may make any further or different provisions that may be practical and
necessary for the circumstances of the emergency.

                                  XI. DIVIDENDS

         11.01. DECLARATION. Subject to such restrictions or requirements as may
be imposed by law or the Company's Articles or as may otherwise be binding upon
the Company, the Board of Directors may from time to time declare dividends on
stock of the Company outstanding on the dates of record fixed by the Board, to
be paid in cash, in property or in shares of the Company's stock on or as of
such payment or distribution dates as the Board may prescribe.

                                 XII. AMENDMENTS

         12.01. PROCEDURE. These Bylaws may be amended, supplemented, repealed
or temporarily or permanently suspended, in whole or in part, or new bylaws may
be adopted, at any duly constituted meeting of the Board of Directors, the
notice of which meeting either includes mention of the proposed action relative
to the Bylaws or is waived as provided in Section 3.04 above. If, however, the
chairman of any such meeting or a majority of directors in attendance thereat in
good faith determines that any such action has arisen as a matter of necessity
at the meeting and is otherwise proper, no notice of such action will be
required.

         12.02. AMENDMENT OF BYLAWS. Notwithstanding any other provision of
these Bylaws, Sections 2.02, 3.01, and 3.12 and Article XII of these Bylaws
shall not be altered, amended, supplemented, repealed, or temporarily or
permanently suspended, in whole or in part, or replacement Bylaw provisions
adopted without: (i) the affirmative vote of a majority of the directors then in
office; and (ii) the affirmative vote of seventy-five percent (75%) or more of
the outstanding shares of the Company entitled to vote generally.

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<PAGE>

                                   CERTIFICATE

         I, NANCY C. LOFTIN, Vice President, General Counsel and Secretary of
ARIZONA PUBLIC SERVICE COMPANY, an Arizona corporation, do HEREBY CERTIFY that
the foregoing is a true and correct copy of the Company's Bylaws, as amended and
that such Bylaws, as amended, are in full force and effect as of the date
hereof.

         IN WITNESS WHEREOF, I have hereunto set my hand and affixed the seal of
said corporation as of this 21st day of January, 2004.

                                   Nancy C. Loftin
                                   ---------------------------------------------
                                   NANCY C. LOFTIN
                                   Vice President, General Counsel and Secretary

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