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                                                                   Exhibit 10.99

                       STOCK OWNERSHIP INCENTIVE AGREEMENT

                                      UNDER
                        PINNACLE WEST CAPITAL CORPORATION
                          2002 LONG-TERM INCENTIVE PLAN

      THIS AWARD AGREEMENT is made and entered into as of _________ ___, 20___
(the "Date of Grant"), by and between Pinnacle West Capital Corporation (the
"Company"), and (FirstName) ("Employee").

                                   BACKGROUND

      A.    The Board of Directors of the Company (the "Board of Directors") has
            adopted, and the Company's shareholders have approved, the Pinnacle
            West Capital Corporation 2002 Long-Term Incentive Plan (the "Plan"),
            pursuant to which stock ownership incentive awards may be granted to
            employees of the Company and its subsidiaries and to certain other
            individuals.

      B.    The Company desires to grant to Employee a stock ownership incentive
            award under the terms of the Plan.

      C.    Pursuant to the Plan, the Company and Employee agree as follows:

                                    AGREEMENT

            1.    DEFINITIONS. For purposes of this Award Agreement, the
                  following terms have the meanings specified in this Section 1:

                  (a)   "AWARD PERIOD" means the period beginning _________ ___,
                        20___ and ending _________ ___, 20___.

                  (b)   "AVERAGE NUMBER OF SHARES OWNED" means (i) the sum of
                        the number of shares of Common Stock (as defined herein)
                        owned by Employee at the _____________ during the Award
                        Period divided by (ii) __________ (___), rounded down to
                        the next whole share.

                  (c)   "AVERAGE SHARE PRICE" means the average _____________
                        price of the Common Stock on the New York Stock Exchange
                        during the Award Period.

                  (d)   "BASE SALARY" means the base salary earned by Employee
                        during the Award Period.

                  (e)   "COMMON STOCK" means the common stock of the Company.

                  (f)   "OWNERSHIP LEVEL" means the Stock Ownership Value (as
                        defined herein) divided by Employee's Base Salary,
                        expressed as a ratio, carried out to two decimal places
                        and rounded down.

                  (g)   "STOCK OWNERSHIP VALUE" means the Average Number of
                        Shares Owned multiplied by the Average Share Price.

            2.    GRANT OF AWARD. Pursuant to action of the Committee (as
                  defined herein), which was taken on the Date of Grant, the
                  Company grants to Employee the stock ownership incentive award
                  described in this Award Agreement.

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Stock Ownership Incentive

            3.    AWARD SUBJECT TO PLAN. This award is granted under and is
                  expressly subject to, all the terms and provisions of the
                  Plan, which terms are incorporated herein by reference, and
                  this Award Agreement. The Committee referred to in Section 4
                  of the Plan ("Committee") has been appointed by the Board of
                  Directors, and designated by it, as the Committee to make
                  awards.

            4.    STOCK OWNERSHIP INCENTIVE AWARD.

                  (a)   GENERAL. Upon satisfaction of the "Threshold Performance
                        Goal" described in Section 4(b) below and the Ownership
                        Level described in Section 4(c) below, the Company will
                        deliver to Employee, as soon as practicable after the
                        end of the Award Period, but no later than _________
                        ___, 20___, a number of shares of Common Stock equal to
                        _____ percent (__%) of Employee's Average Number of
                        Shares Owned, subject to the limitation described in
                        Subsection 4(d) below. Partial shares will be rounded
                        down to the nearest whole share, when applicable.
                        Attachment A provides a generic example of the operation
                        of a Stock Ownership Incentive Award.

                  (b)   THRESHOLD PERFORMANCE GOAL. For purposes of this Award
                        Agreement, the threshold performance goal for the Award
                        Period will have been met if, during the Award Period,
                        the Company's earnings from continuing operations[,
                        excluding the effects of the rate case settlement, plus
                        SunCor Development Company's earnings from discontinued
                        operations] are at least $______ million.

                  (c)   OWNERSHIP LEVEL. For purposes of this Agreement, the
                        Common Stock ownership requirement will have been met if
                        Employee's Ownership Level is at least ___ [insert
                        number].

                  (d)   MAXIMUM AWARD. If Employee's Ownership Level exceeds
                        _______ (__), the number of shares of Common Stock
                        awarded to Employee will be ____ percent (__%) of the
                        number of shares represented by an Ownership Level of
                        _________ (__) or _______________ shares maximum.

            5.    EVIDENCE OF OWNERSHIP.

                  (a)   SHARES HELD IN COMPANY PLANS. Employee is not required
                        to provide ownership evidence of shares of Common Stock
                        owned by Employee and held in any Company-sponsored
                        stock-based plan, such as the Pinnacle West Capital
                        Corporation Investors Advantage Plan or the Pinnacle
                        West Capital Corporation Savings Plan.

                  (b)   SHARES HELD OUTSIDE COMPANY PLANS. Shares of Common
                        Stock owned by Employee outside of Company-sponsored
                        stock-based plans (for example, shares held in a
                        brokerage account) will be included in Employee's
                        Average Number of Shares Owned only if Employee provides
                        the Company with written evidence of such ownership (for
                        example, a copy of a brokerage account statement).
                        Employee must provide the Company with evidence of such
                        ownership no later than thirty (30) days following the
                        end of the Award Period.

            6.    TERMINATION OF AWARD. This Award Agreement will terminate and
                  be of no further force or effect as of the date during the
                  Award Period that Employee is no

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                  longer employed by the Company or any of its subsidiaries,
                  unless the termination of active employment is due to
                  Employee's death or Disability (as defined herein). In the
                  case of Employee's death or Disability, Employee will be
                  deemed to have been employed by the Company through the end of
                  the Award Period. No adjustment will be made to Employee's
                  "Base Salary" calculation as a result of Employee's death or
                  Disability (e.g., the base salary earned by Employee to the
                  date of Employee's death or Disability will not be annualized
                  over the Award Period). For avoidance of doubt, no
                  acceleration of the Award Period will occur as a result of a
                  change of control of the Company.

                  "Disability" shall mean a period of disability during which
                  Employee qualifies for benefits under employer's long-term
                  disability plan, or, if Employee does not participate in such
                  a plan, a period of disability during which Employee would
                  have qualified for benefits under such a plan, as determined
                  by the Committee, had Employee been a participant in such a
                  plan. The Committee may require such medical or other
                  evidence, as it deems necessary to judge the nature of
                  Employee's condition.

            7.    TAX WITHHOLDING. Employee must pay, or make arrangements
                  acceptable to the Company for the payment of, any and all
                  federal, state, and local income and payroll tax withholding
                  that in the opinion of the Company is required by law. Unless
                  Employee satisfies any such tax withholding obligation by
                  paying the amount in cash or by check , the Company will
                  withhold shares of Common Stock having a Fair Market Value on
                  the date of withholding sufficient to cover the withholding
                  obligation.

            8.    NON-TRANSFERABILITY. Neither this award nor any rights under
                  this Award Agreement may be assigned, transferred or in any
                  manner encumbered except by will or the laws of descent and
                  distribution, and any attempted assignment, transfer,
                  mortgage, pledge or encumbrance except as herein authorized,
                  will be void and of no effect.

            9.    DEFINITIONS; COPY OF PLAN AND PLAN PROSPECTUS. To the extent
                  not specifically defined in this Award Agreement, all
                  capitalized terms used in this Award Agreement will have the
                  same meanings ascribed to them in the Plan. By signing this
                  Award Agreement, Employee acknowledges receipt of a copy of
                  the Plan and the related Plan Prospectus.

            10.   CHOICE OF LAW. This Award Agreement will be governed by the
                  laws of the State of Arizona excluding any conflicts or choice
                  of law rule or principle that might otherwise refer
                  construction or interpretation of this Agreement to another
                  jurisdiction.

      An authorized representative of the Company has signed this Award
Agreement, and Employee has signed this Award Agreement to evidence Employee's
acceptance of the award on the terms specified in this Award Agreement, all as
of the Date of Grant.

                                   PINNACLE WEST CAPITAL CORPORATION

                                   By: _________________________________________
                                   Its: Vice President and Treasurer

                                   _____________________________________________
                                   Employee

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                                  ATTACHMENT A

                                 GENERIC EXAMPLE
                        (STOCK OWNERSHIP INCENTIVE AWARD)

ASSUMPTIONS:

      -     Earnings threshold is met.

      -     Employee's Base Salary is $100,000.

      -     Employee's Ownership Level must be at least two (2) (Employee's
            Ownership Level is based on Employee's title) and cannot exceed five
            (5).

      -     Grant of shares at four percent (4%) of Employee's Average Number of
            Shares Owned.

      -     Employee owns 5,800 shares of Common Stock at the end of each month
            during 20___, resulting in the Average Number of Shares Owned
            equaling 5,800.

      -     The Average Share Price for 20___ is $35.00 per share.

      -     Employee's Stock Ownership Value is $203,000 (5,800 shares X $35.00
            per share)

      -     Employee's Ownership Level is $203,000 / $100,000, or 2.03.

      -     Employee meets the required Ownership Level of at least 2.

DELIVERY OF COMMON STOCK TO EMPLOYEE:

      -     Employee would receive 232 shares of Common Stock (4% of 5,800
            shares, rounded down, which represents Employee's Average Number of
            Shares Owned)

APPLICATION OF THE MAXIMUM:

      -     Same assumptions, except Average Number of Shares Owned equals
            15,000.

      -     Employee's Stock Ownership Value is $525,000 (15,000 shares X $35.00
            per share)

      -     Employee's Ownership Level is 525,000 / 100,000, or 5.25.

      -     Shares are not awarded for Ownership Levels above 5, so five times
            Base Salary is $500,000 Stock Ownership Value, resulting in 14,285
            shares ($500,000 / $35 per share). The 4% award would be based on
            14,285 shares; as a result, Employee would receive 571 shares.

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