EXHIBIT 31.2


          CERTIFICATIONS OF PRINCIPAL FINANCIAL AND ACCOUNTING OFFICER
                PURSUANT TO EXCHANGE ACT RULES 13A-14 AND 15D-14
        AS ADOPTED PURSUANT TO SECTION 302 OF SARBANES-OXLEY ACT OF 2002


I, Edward Terino, Senior Vice President of Finance and Chief Financial Officer
of Art Technology Group, Inc., certify that:

     1. I have reviewed this quarterly report on Form 10-Q of Art Technology
Group, Inc. for the quarter ended September 30, 2004;

     2. Based on my knowledge, this report does not contain any untrue statement
of a material fact or omit to state a material fact necessary to make the
statements made, in light of the circumstances under which such statements were
made, not misleading with respect to the period covered by this report;

     3. Based on my knowledge, the financial statements, and other financial
information included in this report, fairly present in all material respects the
financial condition, results of operations and cash flows of the registrant as
of, and for, the periods presented in this report;

     4. The registrant's other certifying officer and I are responsible for
establishing and maintaining disclosure controls and procedures (as defined in
Exchange Act Rules 13a-15(e) and 15d-15(e)) for the registrant and have:

          a) Designed such disclosure controls and procedures, or caused such
     disclosure controls and procedures to be designed under our supervision, to
     ensure that material information relating to the registrant, including its
     consolidated subsidiaries, is made known to us by others within those
     entities, particularly during the period in which this report is being
     prepared;

          b) [Paragraph omitted in accordance with SEC transition instructions
     contained in release 34-47986]

          c) Evaluated the effectiveness of the registrant's disclosure controls
     and procedures and presented in this report our conclusions about the
     effectiveness of the disclosure controls and procedures as of the end of
     the period covered by this report based on such evaluation; and

          d) Disclosed in this report any change in the registrant's internal
     control over financial reporting that occurred during the registrant's most
     recent fiscal quarter (the registrant's fourth fiscal quarter in the case
     of an annual report) that has materially affected, or is reasonably likely
     to materially affect, the registrant's internal control over financial
     reporting; and

     5. The registrant's other certifying officer and I have disclosed, based on
our most recent evaluation of internal control over financial reporting, to the
registrant's auditors and the audit committee of registrant's board of directors
(or persons performing the equivalent functions):

     a) All significant deficiencies and material weaknesses in the design or
operation of internal control over financial reporting which are reasonably
likely to adversely affect the registrant's ability to record, process,
summarize and report financial information; and

     b) Any fraud, whether or not material, that involves management or other
employees who have a significant role in the registrant's internal control over
financial reporting.

                                                 /s/ EDWARD TERINO
                                      ------------------------------------------
                                                     Edward Terino
                                       Senior Vice President, Finance and Chief
                                      Financial Officer (principal financial and
                                                 accounting officer)

Date: November 9, 2004