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                                                                   Exhibit 10.19



Robert Burke
12 Allen Circle
Boxford, MA 01921


March 28, 2003

Dear Bob,

         This letter agreement is intended to set forth and confirm certain of
the terms of your employment by Art Technology Group, Inc. ("ATG" or the
"Company"). This letter agreement supersedes and replaces in all respects the
provisions set forth in the fifth, sixth and seventh paragraphs of the offer
letter between ATG and you dated December 4, 2002. ATG hereby agrees with you as
follows:

         Either you or the Company may terminate your employment at any time
upon at least 10 business days' written notice; provided that if the Company
terminates your employment without Cause, or you resign for Good Reason at any
time, the Company shall:

                  (a) pay you immediately for all accrued but unused vacation
         and wages for time employed,

                  (b) provide outplacement services through one or more outside
         firms of the Company's choosing through the earlier of 12 months
         following the termination date or the date when you secure full time
         employment,

                  (c) continue to pay you your then-current base salary
         distributed at regular pay period intervals for a period of 12 months
         from the date of termination, and

                  (d) continue to provide you with health care coverage for a
         period of 12 months from the date of termination, provided that you
         continue to contribute to such health care coverage at the same rate as
         your contribution prior to the termination date.

Notwithstanding the foregoing, if you become employed by any Competitor of ATG
within the 12-month period following the date of a termination without Cause or
Good Reason then ATG shall cease paying your salary continuation and benefits.
Competitors shall be defined as the following entities: BEA, the IBM Websphere
business unit, Blue Martini, Broadvision, and Vignette.

         "CAUSE" shall mean:

                  (1) your willful and continued failure to substantially
         perform reasonable assigned duties (other than any such failure
         resulting from incapacity due to physical or mental illness or any
         failure after you have given notice of termination for Good Reason),
         which failure is not cured within 30 days after a written demand for
         substantial performance is

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Robert Burke
March 28, 2003
Page 2


         received by the Executive from the Board of Directors of the Company
         which specifically identifies the manner in which the Board of
         Directors believes you have not substantially performed your duties; or

                  (2) your conviction of a felony (other than through vicarious
         liability or involving a vehicular offense) which is materially and
         demonstrably injurious to the Company or a crime involving fraud or
         embezzlement against the Company.

         "GOOD REASON" shall mean the occurrence, without your written consent,
of any of the following events or circumstances:

                  (1) any change to the title of Chief Executive Officer or the
         assignment to you of duties inconsistent in any material respect with
         your positions (including status, offices, titles and reporting
         requirements);

                  (2) a material reduction in any aspect of your compensation,

                  (3) the failure by the Company to

                           (i) continue in effect any material compensation or
                  benefit plan or program consistent with those afforded to
                  other senior executives of the Company (including without
                  limitation any life insurance, medical, health and accident or
                  disability plan and any vacation or automobile program or
                  policy) in which you participate or which is applicable to
                  you,

                           (ii) continue your participation therein (or in such
                  substitute or alternative plan) on a basis not materially less
                  favorable, both in terms of the amount of benefits provided
                  and the level of your participation relative to other
                  participants, than the basis existing immediately prior to the
                  change, or

                           (iii) award cash bonuses to you in amounts and in a
                  manner substantially consistent with and proportional to those
                  awarded to other senior executives;

                  (4) any alteration in the Company's 1996 Amended and Restated
         Stock Option Plan in any manner

         that may exert an adverse impact on you for the grant of the option
         agreements granted to you as of December 4, 2002 and January 2, 2003
         (the "Option Agreements");

                  (5) a change by the Company in the location at which you
         perform your principal duties to a new location that is both (i)
         outside a radius of 35 miles from your principal residence immediately
         prior to the change and (ii) more than 20 miles from the location at
         which you performed your principal duties immediately prior to the
         change;
                  (6) the material breach of this letter agreement by the
         Company;

                  (7) the failure of the Company to obtain the agreement from
         any successor to the Company to assume and perform the provisions set
         forth in this letter agreement; or

                  (8) if, as a result of a Change of Control, as defined in the
         Option Agreements, the Company no longer has a publicly traded class of
         equity securities and/or is no longer subject to reporting requirements
         under the Securities Exchange Act of 1934.

         Each reference in the Option Agreements to the Offer Letter dated
December 4, 2002 shall, as of the date hereof, be deemed to refer to this letter
agreement.

         The validity, interpretation, construction and performance of this
letter agreement shall be governed by the internal laws of the Commonwealth of
Massachusetts, without regard to

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Robert Burke
March 28, 2003
Page 3


conflicts of law principles, and any disputes shall be resolved by final and
binding arbitration to be conducted in the Greater Boston, MA area pursuant to
American Arbitration Association's rules for the resolution of employment
disputes. This letter agreement may be amended or modified only by a written
instrument executed by both the Company and you.

         The parties are executing this letter agreement under seal as of the
date set forth above.

Art Technology Group, Inc.


 /s/ Paul Shorthose
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Paul Shorthose
Working Chairman

I accept the terms above.

 /s/ Robert Burke
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Robert Burke