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                                                                      Exhibit 11

                         CMP Media Inc. and Subsidiaries
                     Computation of Pro Forma Net Income Per
                       Common and Common Equivalent Share
                      (in thousands, except share amounts)
                                    unaudited

<TABLE>
<CAPTION>
                                                         Three months ended         Nine months ended
                                                            September 30,             September 30,
                                                      ------------------------  ------------------------
                                                          1996         1997         1996         1997
                                                      -----------  -----------  -----------  -----------
<S>                                                   <C>          <C>          <C>          <C>        
Historical income before provision for income taxes   $     8,571  $     6,676  $    16,970  $    14,193
Pro forma provision for income taxes assuming
 change in tax status to C corporation prior to
 January 1, 1996                                            3,614        2,911        7,156        6,188
                                                      -----------  -----------  -----------  -----------
Pro forma net income applicable to common and
 common equivalent shares                             $     4,957  $     3,765  $     9,814  $     8,005
                                                      ===========  ===========  ===========  ===========
Primary shares:
 Weighted average number of common stock and
 common stock equivalents outstanding:
   Common stock                                        18,874,570   21,697,904   18,874,570   19,815,681
   Options                                              1,291,753    1,643,182    1,291,753    1,408,896
   Shares required to be issued to pay S corporation
    Distribution                                        1,727,273      575,758    1,727,273    1,343,435
   Shares required to be issued to pay S corporation
    distributions in excess of earnings during the
    previous twelve months                                468,181      156,060      468,181      364,141
                                                      -----------  -----------  -----------  -----------
                                                       22,361,777   24,072,904   22,361,777   22,932,153
                                                      ===========  ===========  ===========  ===========
Fully diluted shares:
 Weighted average number of common stock and
 common stock equivalents outstanding:
   Common stock                                        18,874,570   21,697,904   18,874,570   19,815,681
   Options                                              1,291,753    1,643,182    1,291,753    1,408,896
   Shares required to be issued to pay S corporation
    Distribution                                        1,727,273      575,758    1,727,273    1,343,435
   Shares required to be issued to pay S corporation
    distributions in excess of earnings during the
    previous twelve months                                468,181      156,060      468,181      364,141
                                                      -----------  -----------  -----------  -----------
                                                       22,361,777   24,072,904   22,361,777   22,932,153
                                                      ===========  ===========  ===========  ===========
</TABLE>