<ARTICLE> 5
<MULTIPLIER> 1,000
       
                                                  
<PERIOD-TYPE>                   3-MOS                   3-MOS
<FISCAL-YEAR-END>                          DEC-31-1997             DEC-31-1996
<PERIOD-START>                             JAN-01-1997             JAN-01-1996
<PERIOD-END>                               MAR-31-1997             MAR-31-1996
<CASH>                                          12,789                   4,272
<SECURITIES>                                    10,730                  22,725
<RECEIVABLES>                                   45,678                  36,405
<ALLOWANCES>                                     1,339                   1,469
<INVENTORY>                                      4,441                   3,832
<CURRENT-ASSETS>                                76,922                  69,881
<PP&E>                                          46,005                  30,491
<DEPRECIATION>                                  17,438                  10,983
<TOTAL-ASSETS>                                 260,380                 174,200
<CURRENT-LIABILITIES>                           36,694                  25,301
<BONDS>                                              0                       0
<PREFERRED-MANDATORY>                                0                       0
<PREFERRED>                                          0                       0
<COMMON>                                           250                     226
<OTHER-SE>                                     201,630                 140,980
<TOTAL-LIABILITY-AND-EQUITY>                   260,380                 174,200
<SALES>                                              0                       0
<TOTAL-REVENUES>                                51,944                  41,506
<CGS>                                                0                       0
<TOTAL-COSTS>                                   46,591                  38,492
<OTHER-EXPENSES>                                     0                       0
<LOSS-PROVISION>                                     0                       0
<INTEREST-EXPENSE>                                 209                     264
<INCOME-PRETAX>                                  5,705                   3,248
<INCOME-TAX>                                     2,258                   1,469
<INCOME-CONTINUING>                                  0                       0
<DISCONTINUED>                                       0                       0
<EXTRAORDINARY>                                      0                       0
<CHANGES>                                            0                       0
<NET-INCOME>                                     3,447                   1,779
<EPS-PRIMARY>                                     0.14                    0.08
<EPS-DILUTED>                                     0.13                    0.07