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                                                                   Exhibit 10.23

                           AMERICA SERVICE GROUP INC.

                 AMENDED AND RESTATED 1999 INCENTIVE STOCK PLAN

                             INCENTIVE STOCK OPTION

                               OPTION CERTIFICATE

America Service Group Inc. ("ASG"), a Delaware corporation, in accordance with
the America Service Group Inc. Amended and Restated 1999 Incentive Stock Plan,
hereby grants an Option to _______________, who shall be referred to as
"Employee," to purchase from ASG ________ shares of Stock at an Option Price per
share equal to $________, which grant shall be subject to all of the terms and
conditions set forth in this Option Certificate and in the Plan. This grant has
been made as of _____________, 20___, which shall be referred to as the "Grant
Date." This Option is intended to satisfy the requirements of Section 422 of the
Code and thus is intended to be an ISO as that term is defined in the Plan.

                                  AMERICA SERVICE GROUP INC.

                                  By:_________________________________________


Acknowledged:                     EMPLOYEE

                                  ____________________________________________

                                  Date:_______________________________________

                              TERMS AND CONDITIONS

      Section 1. Plan. This Option grant is subject to all the terms and
conditions set forth in the Plan and this Option Certificate, and all the terms
in this Option Certificate which begin with a capital letter are either defined
in this Option Certificate or in the Plan. If a determination is made that any
term or condition set forth in this Option Certificate is inconsistent with the
Plan, the Plan

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shall control. A copy of the Plan will be made available to Employee upon
written request to the Committee.

            Section 2. Vesting and Option Expiration.

            (a)   General Rule. Subject to Section 2(b) and Section 2(c),
                  Employee's right under this Option Certificate to exercise
                  this Option shall vest with respect to:

                  (1)   one-third of the non-vested shares of Stock which are
                        subject to this Option on the first anniversary of the
                        Grant Date provided he or she remains continuously
                        employed by ASG through the first anniversary of the
                        Grant Date,

                  (2)   one-third of the non-vested shares of Stock which remain
                        subject to this Option on the second anniversary of the
                        Grant Date provided he or she remains continuously
                        employed by ASG through the second anniversary of the
                        Grant Date, and

                  (3)   the remaining non-vested shares of Stock which are
                        subject to this Option on the third anniversary of the
                        Grant Date provided he or she remains continuously
                        employed by ASG through the third anniversary of the
                        Grant Date.

            (b)   Option Expiration Rules.

                  (1)   Non-Vested Shares. If Employee's employment with ASG
                        terminates for any reason whatsoever, including death,
                        disability (as determined under ASG's long-term
                        disability plan) or retirement, while there are any
                        non-vested shares of Stock subject to this Option
                        under Section 2(a), this Option immediately upon such
                        termination of employment shall expire and shall have no
                        further force or effect and be null and void with
                        respect to such non-vested shares of Stock.

                  (2)   Vested Shares. Employee's right to exercise all or any
                        part of this Option which has vested under Section 2(a)
                        shall expire no later than the tenth anniversary of the
                        Grant Date. However, if Employee's employment with ASG
                        terminates before the tenth anniversary of the Grant
                        Date, Employee's right to exercise this Option which has
                        vested under Section 2(a) shall expire and shall have no
                        further force or effect and shall be null and void

                        (A)   on the date his or her employment terminates if
                              his or her

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                              employment terminates for cause (as determined by
                              the Committee),

                        (B)   on the first anniversary of the date his or her
                              employment terminates if his or her employment
                              terminates as a result of his or her death or
                              disability (as determined under ASG's long-term
                              disability plan), or

                        (C)   at the end of the 90-day period which starts on
                              the date his or her employment terminates if his
                              or her employment terminates other than (1) for
                              cause (as determined by the Committee) or (2) as a
                              result of his or her death or disability (as
                              determined under ASG's long-term disability plan).

            (c)   Special Rules.

                  (1)   Change in Control. If there is a Change in Control of
                        ASG, this Option shall be subject to the provisions of
                        Section 14 of the Plan with respect to such Change in
                        Control.

                  (2)   Affiliates. For purposes of this Option Certificate, any
                        reference to ASG shall include any Affiliate, Parent or
                        Subsidiary of ASG, and a transfer of employment between
                        ASG and any Affiliate, Parent or Subsidiary of ASG or
                        between any Affiliate, Parent or Subsidiary of ASG shall
                        not be treated as a termination of employment under the
                        Plan or this Option Certificate.

                  (3)   Fractional Shares. Employee's right to exercise this
                        Option shall not include a right to exercise this Option
                        to purchase a fractional share of Stock. If Employee
                        exercises this Option on any date when this Option
                        includes a fractional share of Stock, his or her
                        exercise right shall be rounded down to the nearest
                        whole share of Stock and the fractional share shall be
                        carried forward until that fractional share together
                        with any other fractional shares can be combined to
                        equal a whole share of Stock or this Option expires.

      Section 3. Method of Exercise of Option. Employee may exercise this Option
in whole or in part (to the extent this Option is otherwise exercisable under
Section 2 with respect to vested shares of Stock) only in accordance with the
rules and procedures established from time to time by ASG for the exercise of an
Option. The Option Price shall be paid at exercise either in cash, by check
acceptable to ASG, by tendering to ASG shares of Stock registered in Employee's
name which have been held for at least six months or through any cashless
exercise/resale procedure which is

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implemented by a broker unrelated to ASG through a sale of Stock in the open
market and which is acceptable to the Committee, or in any combination of these
forms of payment.

      Section 4. Delivery and Other Laws. ASG shall deliver appropriate and
proper evidence of ownership of any Stock purchased pursuant to the exercise of
this Option as soon as practicable after such exercise to the extent such
delivery is then permissible under applicable law or rule or regulation, and
such delivery shall discharge ASG of all of its duties and responsibilities with
respect to this Option.

      Section 5. Nontransferable. Except as expressly authorized by the
Committee, no rights granted under this Option shall be transferable by Employee
other than by will or by the laws of descent and distribution, and the rights
granted under this Option shall be exercisable during Employee's lifetime only
by Employee. The person or persons, if any, to whom this Option is transferred
by will or by the laws of descent and distribution shall be treated after
Employee's death the same as Employee under this Option Certificate.

      Section 6. No Right to Continue Service. Neither the Plan, this Option,
nor any related material shall give Employee the right to continue in employment
by ASG or shall adversely affect the right of ASG to terminate Employee's
employment with or without cause (as determined by the Committee) at any time.

      Section 7. Stockholder Status. Employee shall have no rights as a
stockholder with respect to any shares of Stock under this Option until such
shares have been duly issued and delivered to Employee, and no adjustment shall
be made for dividends of any kind or description whatsoever or for distributions
of rights of any kind or description whatsoever respecting such Stock except as
expressly set forth in the Plan.

      Section 8. Governing Law. The Plan and this Option shall be governed by
the laws of the State of Delaware.

      Section 9. Binding Effect. This Option shall be binding upon ASG and
Employee and their respective heirs, executors, administrators and successors.

      Section 10. Tax Withholding. This Option has been granted subject to the
condition that Employee consents to whatever action the Committee directs to
satisfy the minimum statutory federal and state withholding requirements, if
any, which ASG determines are applicable upon the exercise of this Option.

      Section 11. References. Any references to sections (Section) in this
Option Certificate shall be to sections (Section) of this Option Certificate
unless otherwise expressly stated as part of such reference.

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