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                                                                     Exhibit 11


                       UNITED ASSET MANAGEMENT CORPORATION
                        CALCULATION OF EARNINGS PER SHARE
                    (In thousands, except per-share amounts)
                                   (Unaudited)


<TABLE>
<CAPTION>
---------------------------------------------------------------------------------------------------------------------------
                                                For the Three Months Ended June 30,     For the Six Months Ended June 30,
----------------------------------------------------------------------------------    -------------------------------------
                                                 Income        Shares    Per-Share      Income        Shares      Per-Share
                                               (Numerator)  (Denominator)  Amount     (Numerator)  (Denominator)    Amount
----------------------------------------------------------------------------------    -------------------------------------
<S>                                            <C>            <C>           <C>       <C>            <C>             <C>  

For the three- and six-month periods 
  ended June 30, 1998 
Basic Earnings per Share 
Income available to common shareholders        $22,117,000    67,636,000    $.33      $44,215,000    68,586,000      $.64 
                                                                            ====                                     ====
                                                                                                                        
Effect of Dilutive Securities (1)                       --     2,382,000                       --     2,364,000           
                                               -----------    ----------              -----------    ----------
Diluted Earnings per Share                                                                                              
Income available to common                                                                                              
  shareholders + assumed conversions           $22,117,000    70,018,000    $.32      $44,215,000    70,950,000      $.62
                                               ===========    ==========    ====      ===========    ==========      ====
================================================================================      ===================================
For the three- and six-month periods                                                                                    
  ended June 30, 1997                                                                                                   
Basic Earnings per Share                                                                                                
Income available to common shareholders        $24,030,000    69,865,000    $.34      $48,085,000    69,600,000      $.69
                                                                            ====                                     ====
                                                                                                                        
Effect of Dilutive Securities (2)                       --     3,145,000                       --     3,644,000          
                                               -----------    ----------              -----------    ----------

Diluted Earnings per Share                                                                                              
Income available to common                                                                                              
  shareholders + assumed conversions           $24,030,000    73,010,000    $.33      $48,085,000    73,244,000      $.66
                                               ===========    ==========    ====      ===========    ==========      ====
================================================================================      ===================================
                                               
</TABLE>


(1)  Options on 1,647,000 and 1,731,000 shares of common stock and warrants on
     1,521,000 and 1,526,000 shares of common stock were outstanding during the
     three- and six-month periods ended June 30, 1998, respectively, but were
     not included in computing diluted earnings per share because their effects
     were antidilutive.

(2)  Options on 1,271,000 and 717,000 shares of common stock and warrants on
     957,000 and 833,000 shares of common stock were outstanding during the
     three- and six-month periods ended June 30, 1997, respectively, but were
     not included in computing diluted earnings per share because their effects
     were antidilutive.