<TABLE> <S> <C>

<PAGE>
 
<ARTICLE> 5
<LEGEND>
THIS SCHEDULE CONTAINS SUMMARY FINANCIAL INFORMATION EXTRACTED FROM THE
CONSOLIDATED FINANCIAL STATEMENTS INCLUDED IN THE FORM 10-Q AND IS QUALIFIED IN
ENTIRETY TO REFERENCE TO SUCH FINANCIAL STATEMENTS. THE AMOUNTS BELOW HAVE BEEN
RESTATED TO REFLECT A BUSINESS COMBINATION ACCOUNTED FOR BY A POOLING OF
INTERESTS
</LEGEND>
<MULTIPLIER> 1,000
<RESTATED>
       
<S>                             <C>                     <C>
<PERIOD-TYPE>                   3-MOS                   3-MOS
<FISCAL-YEAR-END>                          DEC-31-1998             DEC-31-1997
<PERIOD-START>                             JAN-01-1998             JAN-01-1997
<PERIOD-END>                               MAR-31-1998             MAR-31-1997
<CASH>                                          83,412                  43,830
<SECURITIES>                                         0                       0
<RECEIVABLES>                                   70,663                  40,047
<ALLOWANCES>                                     1,311                     869
<INVENTORY>                                          0                       0
<CURRENT-ASSETS>                               166,031                  90,357
<PP&E>                                          13,495                   7,365
<DEPRECIATION>                                   3,161                   1,790
<TOTAL-ASSETS>                                 178,292                  95,932
<CURRENT-LIABILITIES>                           47,696                  40,854
<BONDS>                                              0                       0
<PREFERRED-MANDATORY>                                0                       0
<PREFERRED>                                          0                       0
<COMMON>                                           490                     233
<OTHER-SE>                                     128,250                  51,722
<TOTAL-LIABILITY-AND-EQUITY>                   178,292                  49,588
<SALES>                                              0                       0
<TOTAL-REVENUES>                                81,586                  48,339
<CGS>                                           55,283                  34,758
<TOTAL-COSTS>                                   70,647                  55,090
<OTHER-EXPENSES>                                     0                       0
<LOSS-PROVISION>                                   353                     250
<INTEREST-EXPENSE>                                   0                       0
<INCOME-PRETAX>                                 11,611                   3,867
<INCOME-TAX>                                     4,667                   1,698
<INCOME-CONTINUING>                              6,944                   2,169
<DISCONTINUED>                                       0                       0
<EXTRAORDINARY>                                      0                       0
<CHANGES>                                            0                       0
<NET-INCOME>                                     6,944                   2,169
<EPS-PRIMARY>                                     0.14                    0.05
<EPS-DILUTED>                                     0.14                    0.05
        

</TABLE>