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                                                                   Exhibit 10.21

                           AMERICA SERVICE GROUP INC.

                 AMENDED AND RESTATED 1999 INCENTIVE STOCK PLAN

                           NON-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 ____________________, a non-employee member of the
Board of Directors of ASG who shall be referred to as "Optionee," 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 not
intended to satisfy the requirements of Section 422 of the Code and thus shall
be a Non-ISO as that term is defined in the Plan.

                                     AMERICA SERVICE GROUP INC.

                                     By:_____________________________________


Acknowledged:                        OPTIONEE

                                     ________________________________________

                                     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 Optionee upon
written request to the Committee.

      Section 2. Vesting and Option Expiration.

      (a)   General Rule. Subject to Section 2(b) and Section 2(c), this Option
            shall vest as follows:

            (1)   This option may not be exercised during the first year from
                  the date hereof. Thereafter, it may only be exercised to a
                  maximum cumulative extent of 25% of the total shares covered
                  by this option in the second year from the date hereof, 50% of
                  the total shares in the third year from the date hereof, and
                  75% of the total shares in the fourth year from the date
                  hereof. After the end of the fourth year from the date hereof,
                  this Option, to the extent not previously exercised, may be
                  exercised in full.

      (b)   Option Expiration Rules.

            (1)   Non-Vested Shares. If Optionee's service on the Board of
                  Directors of 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
                  service 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. This option may not be exercised after the
                  earliest to occur of any of the following:

                  (A)   more than three (3) months after the termination of
                        Optionee's service on the Board of Directors of ASG for
                        any reason other than death (and then only to the extent
                        the Optionee could have exercised this option on the
                        date of termination); or,

                  (B)   more than twelve (12) months after death, if death
                        occurs while the Optionee is serving on the Board of
                        Directors of ASG (and then only to the extent the
                        Optionee could have exercised this option on the date of
                        his death); or

                  (C)   more than 10 years from the date hereof.

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      (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.

            (3)   Fractional Shares. Optionee's right to exercise this Option
                  shall not include a right to exercise this Option to purchase
                  a fractional share of Stock. If Optionee 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. Optionee 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 Optionee's
name which have been held for at least six months or through any cashless
exercise/resale procedure which is 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 Optionee
other than by will or by the laws of descent and distribution, and the rights
granted under this Option shall be exercisable during Optionee's lifetime only
by Optionee. 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
Optionee's death the same as Optionee under this Option Certificate.

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      Section 6. Stockholder Status. Optionee 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 Optionee, 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 7. Governing Law. The Plan and this Option shall be governed by
the laws of the State of Delaware.

      Section 8. Binding Effect. This Option shall be binding upon ASG and
Optionee and their respective heirs, executors, administrators and successors.

      Section 9. Tax Withholding. This Option has been granted subject to the
condition that Optionee 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 10. 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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