Thirty-five businesses appear in both the owners' NMHC 50 and the managers' NMHC 50. Consequently, on each list there are 15 companies that appear on that list only. (Closely affiliated companies are included in the count of 35. These pairs are Whitehall Real Estate/Archon Management, FowlerShore & Flanagan/Trust Property Management, and TVO Real Estate Services/EPT Management.) Many of the firms appearing on just one of the lists both own and manage apartment properties, but they specialize in either one or the other. The specialists include some of the biggest companies on the two lists. Among apartment owners, Related Capital and Boston Capital have long been near the top of the NMHC 50 even though Related uses other companies to manage many of its properties and Boston Capital contracts out all of its property management. Similarly, on the managers' NMHC 50, Pinnacle Realty Management is No. 4 this year, managing over 90,000 apartments, while their ownership interests fall just short of the threshold for the ownership NMHC 50.

Even as some of the biggest specialists continue to grow, the trend overall has been toward joint ownership and management. Last year there were 21 specialists on each of the two NMHC 50 rankings, and in 1997 there were 25. The growing presence of REITs, which typically manage most of what they own, helps explain the decreasing number of specialists in the rankings.

Finally, some firms that appear on both the ownership and management NMHC 50 lists are more prominent in one ranking than the other. AIMCO is the standout example, managing 114,363 more apartments than they own, even though they rank No. 1 in ownership as well.

Others whose ownership and management portfolios differ by more than 10,000 apartments are Boston Financial, LeFrak Organization, Lincoln Property Co., Forest City Residential Group, Post Properties, Gables Residential Trust, and Associated Estates Realty Corp.