<ARTICLE> 5
<LEGEND>
THIS SCHEDULE CONTAINS SUMMARY FINANCIAL INFORMATION EXTRACTED FROM FORRESTER
RESEARCH, INC.'S DECEMBER 31, 1998 CONSOLIDATED FINANCIAL STATEMENTS AND IS
QUALIFIED IN ITS ENTIRETY BY REFERENCE TO SUCH FINANCIAL STATEMENTS CONTAINED IN
FORM 10-K.
</LEGEND>
<CURRENCY> U.S. DOLLARS

                             
<PERIOD-TYPE>                   3-MOS
<FISCAL-YEAR-END>                          DEC-31-1999
<PERIOD-START>                             JUL-01-1999
<PERIOD-END>                               SEP-30-1999
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<ALLOWANCES>                                   400,000
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<PP&E>                                      13,906,283
<DEPRECIATION>                               6,409,827
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