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                                                                      EXHIBIT 11
 
                       COMPUTATION OF PER SHARE EARNINGS
 
               COMPLETE BUSINESS SOLUTIONS, INC. AND SUBSIDIARIES
                PRO FORMA OR ACTUAL NET INCOME PER COMMON SHARE
                     (IN THOUSANDS, EXCEPT PER SHARE DATA)
                                  (UNAUDITED)
 


                                                                THREE MONTHS ENDED
                                                                  SEPTEMBER 30,
                                                                ------------------
                                                                 1998       1997
                                                                -------    -------
                                                                     
Weighted average number of shares of Common Stock
  outstanding...............................................     34,539     31,031
Common Stock equivalents calculated using the weighted
  average stock price per share for the periods presented...      1,758      2,380
                                                                -------    -------
Weighted average shares outstanding.........................     36,297     33,411
                                                                =======    =======
Pro forma net income........................................    $ 1,270    $ 3,512
                                                                =======    =======
Pro forma net income per common share.......................    $  0.03    $  0.11
                                                                =======    =======
                                                                NINE MONTHS ENDED
                                                                  SEPTEMBER 30,
                                                                ------------------
                                                                 1998       1997
                                                                -------    -------
Weighted average number of shares of Common Stock
  outstanding...............................................     34,172     29,189
Common Stock equivalents calculated using the weighted
  average stock price per share for the periods presented...         --      1,821
Stock options and convertible stock issued during the twelve
  months immediately preceding the offering date............         --        133
Stock issued to satisfy S corporation distribution based
  upon the estimated initial public offering price per
  share.....................................................         --         --
                                                                -------    -------
Weighted average shares outstanding.........................     34,172     31,143
                                                                =======    =======
Pro forma net income (loss).................................    $(1,087)   $ 8,832
                                                                =======    =======
Pro forma net income (loss) per common share................    $ (0.03)   $  0.28
                                                                =======    =======