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                                                                    EXHIBIT 10.2

                                                      As adopted by the Board of
                                                      Directors on July 19, 2005

                           ART TECHNOLOGY GROUP, INC.

                     NON-EMPLOYEE DIRECTOR COMPENSATION PLAN

      This Non-Employee Director Compensation Plan (this "Plan") is being
adopted to establish the compensation of the Non-Employee Directors of Art
Technology Group, Inc. (the "Company") for fiscal year 2005 and subsequent
fiscal years.

      ELIGIBILITY: Each member of the Company's Board of Directors who is not an
employee of the Company shall be eligible to participate in the Plan (the
"Non-Employee Directors").

      ANNUAL RETAINER: Each Non-Employee Director shall receive an annual
retainer in the amount of $10,000, shall be payable in quarterly installments in
arrears.

      STOCK OPTIONS: Each Non-Employee Director shall receive an annual option
grant covering 25,000 shares of common stock of the Company (the "Common
Stock"), to be granted each year on the date of the Company's Annual Meeting of
Stockholders (or such later date on which a Non-Employee Director shall first be
elected), which option shall have an exercise price equal to the fair market
value of the Common Stock on the date of grant and shall vest in equal quarterly
installments; provided, however, that for fiscal year 2005 this annual option
grant shall be granted on the date that this Plan is adopted, but vest as if
such grant had been made on the date of the Company's 2005 Annual Meeting of
Stockholders.

      RESTRICTED STOCK: Each Non-Employee Director shall receive an annual
restricted stock grant of a number of shares of the Common Stock equal to $2,500
divided by the fair market value of the Common Stock on the date of grant, which
grant shall vest in equal quarterly installments and be made on the date of the
Company's Annual Meeting of Stockholders (or such later date on which a
Non-Employee Director shall first be elected); provided, however, that for
fiscal year 2005 this annual restricted stock grant shall be granted on the date
that this Plan is adopted, but vest as if such grant had been made on the date
of the Company's 2005 Annual Meeting of Stockholders.

      ADDITIONAL ANNUAL RETAINER FOR CHAIRS: Each Non-Employee Director shall
receive an annual retainer of $7,500, payable in quarterly installments in
arrears, for each chair of the Board of Directors or the Audit, Compensation, or
Nominating and Governance Committee thereof held by such Non-Employee Director.

      MEETING FEES: Each Non-Employee Director shall also receive the following
meeting fees:

          (i)   meeting fee of $1,500 for each in person meeting of the Board of
                Directors attended;

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          (ii)  meeting fee of $1,000 for each in person meeting of the Audit,
                Compensation, or Nominating and Governance Committee of the
                Board of Directors attended; and

          (iii) meeting fee of $500 for each telephone meeting of the Board of
                Directors or the Audit, Compensation, or Nominating and
                Governance Committee thereof attended.

      AMENDMENT AND INTERPRETATION: This Plan may be amended at any time by the
Board of Directors of the Company. Any dispute or ambiguity concerning the
application of the terms of this Plan shall be resolved by a determination of
the Board of Directors of the Company, in its sole discretion.