UNITED STATES

                       SECURITIES AND EXCHANGE COMMISSION

                              WASHINGTON, DC 20549

                                    ---------

                                    FORM 8-K


                                 CURRENT REPORT
                     PURSUANT TO SECTION 13 OR 15(d) OF THE
                         SECURITIES EXCHANGE ACT OF 1934


       Date of report (Date of earliest event reported): October 25, 2005


                           ART TECHNOLOGY GROUP, INC.
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             (Exact Name of Registrant as Specified in its Charter)


         Delaware                    000-26679                  04-3141918
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(State or Other Jurisdiction        (Commission               (IRS Employer
     of Incorporation)              File Number)           Identification No.)


25 First Street, Cambridge, Massachusetts                       02141
(Address of Principal Executive Offices)                      (Zip Code)


Registrant's telephone number, including area code: (617) 386-1000
                                                    --------------

Check the appropriate box below if the Form 8-K filing is intended to
simultaneously satisfy the filing obligation of the registrant under any of the
following provisions:

[_]  Written communications pursuant to Rule 425 under the Securities Act (17
     CFR 230.425)

[_]  Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR
     240.14a-12)

[_]  Pre-commencement communications pursuant to Rule 14d-2(b) under the
     Exchange Act (17 CFR 240.14d-2(b))

[_]  Pre-commencement communications pursuant to Rule 13e-4(c) under the
     Exchange Act (17 CFR 240.13e-4(c))



Item 2.02 Results of Operations and Financial Condition.

         Today we issued a press release announcing our results of operations
for the quarter ended September 30, 2005. A copy of the press release is
attached as Exhibit 99.1 to this current report on Form 8-K and is incorporated
by reference herein.

         The information contained in Item 2.02 of this report and Exhibit 99.1
attached hereto shall not be deemed "filed" for purposes of Section 18 of the
Securities Exchange Act of 1934 or otherwise subject to the liabilities of that
section, nor shall it be deemed incorporated by reference in any filing under
the Securities Act of 1933 or the Securities Exchange Act of 1934, except as
expressly set forth by specific reference in such a filing.



Item 9.01 Financial Statements and Exhibits.

         (c)  Exhibits

        Exhibit
        Number          Description
         99.1           October 25, 2005 press release






                                   SIGNATURES

         Pursuant to the requirements of the Securities Exchange Act of 1934,
the registrant has duly caused this report to be signed on its behalf by the
undersigned hereunto duly authorized.

                                             ART TECHNOLOGY GROUP, INC.



Date: October 25, 2005                      By:  /s/ Julie M.B. Bradley      
                                            ---------------------------------
                                                     Julie M.B. Bradley
                                                     Senior Vice President 
                                                     and Chief Financial
                                                     Officer







                                  Exhibit Index

        Exhibit
        Number          Description
         99.1           October 25, 2005 press release