EXHIBIT 21

Subsidiaries of Registrant

|Name (2)                                |  | Place of Incorporation
or Formation |  | Percentage of Voting
Securities of
Subsidiaries Owned
by Registrant as of
December 31, 2007 |  
|--------------------------------------- |  | ----------------------------------- |  | ------------------------------------------------------------------------------------------- | -
|Investment Company of B&R, Inc.         |  | Delaware                            |  | 100.0                                                                                       | %
|B&R Sudley Corporation                  |  | Virginia                            |  | 100.0                                                                                       | %
|WMC Management Co., Inc.                |  | District of Columbia                |  | 100.0                                                                                       | %
|B&R Waterfront Properties, LLC          |  | District of Columbia                |  | 54.0                                                                                        | %
|Ft. Hill Office Associates, LLC         |  | Virginia                            |  | 80.0                                                                                        | %
|Springfield Realty Investors, LLC       |  | Virginia                            |  | 100.0                                                                                       | %
|Waterfront Associates, LLC (1)          |  | District of Columbia                |  | 50.0                                                                                        | %
|EGAP Corporation                        |  | Maryland                            |  | 100.0                                                                                       | %
|Redwood Commercial Management, LLC (1)  |  | Virginia                            |  | 50.0                                                                                        | %
|900 Northbrook Owner, LP                |  | Pennsylvania                        |  | 90.6                                                                                        | %
|Northbrook Development Parcel Owner, LP |  | Pennsylvania                        |  | 100.0                                                                                       | %
|Fountains Owner, LLC                    |  | Delaware                            |  | 100.0                                                                                       | %
|Victoria Place Apartments, LLC          |  | Florida                             |  | 85.0                                                                                        | %
|B&R Investments (PA) L.P.               |  | Pennsylvania                        |  | 97.6                                                                                        | %
|B.R. Properties Owner, LP               |  | Pennsylvania                        |  | 97.6                                                                                        | %
|One Northbrook Owner, LLP               |  | Pennsylvania                        |  | 100.0                                                                                       | %
|220 West Germantown Pike Owner, LP      |  | Pennsylvania                        |  | 98.1                                                                                        | %
|Seaside Investor, LLC                   |  | Maryland                            |  | 51.0                                                                                        | %
|400 South Philadelphia Developers, LLC  |  | Maryland                            |  | 51.0                                                                                        | %
|Laguna Vista Company, Inc.              |  | Maryland                            |  | 100.0                                                                                       | %
|B&R 5160 Parkstone Owner, LLC           |  | Virginia                            |  | 100.0                                                                                       | %
|B&R 919, LLC                            |  | Delaware                            |  | 100.0                                                                                       | %
|Crisfield Borrower, LLC                 |  | Maryland                            |  | 51.0                                                                                        | %
|Jersey Island Owner, LLC                |  | Maryland                            |  | 51.0                                                                                        | %
|4259 West Swamp Road Owner, LP          |  | Pennsylvania                        |  | 100.0                                                                                       | %
|B&R Devon Owner, LP (1)                 |  | Pennsylvania                        |  | 5.5                                                                                         | %
|955 Mearns Road Owner, LP               |  | Pennsylvania                        |  | 97.0                                                                                        | %
|Mearns Unit 2 Owner, LP                 |  | Pennsylvania                        |  | 97.0                                                                                        | %
|B&R Six Valley Square Owner, LP         |  | Pennsylvania                        |  | 100.0                                                                                       | %
|510 E. Township Line Road Owner, LP     |  | Pennsylvania                        |  | 95.0                                                                                        | %
|Blue Bell Valley Square Owner, LP       |  | Pennsylvania                        |  | 96.3                                                                                        | %
|4259 West Swamp Road Owner, LP          |  | Pennsylvania                        |  | 100.0                                                                                       | %
|B&R 10333 Harwin Drive Owner, LP        |  | Delaware                            |  | 100.0                                                                                       | %
|B&R 1100 NASA Parkway Owner, LP         |  | Delaware                            |  | 100.0                                                                                       | %
|B&R 1110 NASA Parkway Owner, LP         |  | Delaware                            |  | 100.0                                                                                       | %
|B&R 1120 NASA Parkway Owner, LP         |  | Delaware                            |  | 100.0                                                                                       | %
|B&R 17043-49 El Camino Owner, LP        |  | Delaware                            |  | 100.0                                                                                       | %
|B&R 1717 Portway Plaza Owner, LP        |  | Delaware                            |  | 100.0                                                                                       | %
|B&R 8700 Commerce Drive Owner, LP       |  | Delaware                            |  | 100.0                                                                                       | %
|B&R 9950 Westpark Owner, LP             |  | Delaware                            |  | 100.0                                                                                       | %
|Huntington at Sundance Owner, LP        |  | Florida                             |  | 100.0                                                                                       | %
|950 Threadneedle Owner, LLC             |  | Delaware                            |  | 100.0                                                                                       | %
|B&R CPN Owner, LP                       |  | Delaware                            |  | 100.0                                                                                       | %
|Holliday Master, LLC (1)                |  | Maryland                            |  | 51.0                                                                                        | %
|Guilford Properties Master (1)          |  | Maryland                            |  | 51.0                                                                                        | %
|Venice Lofts Associates LP (1)          |  | Pennsylvania                        |  | 22.0                                                                                        | %
|Symphony House Associates LP (1)        |  | Pennsylvania                        |  | 22.0                                                                                        | %
|14800 St. Mary's Lane Owner, LLC        |  | Delaware                            |  | 100.0                                                                                       | %
|14825 St. Mary's Lane Owner, LLC        |  | Delaware                            |  | 100.0                                                                                       | %
|Westbury Owner, LLC                     |  | Delaware                            |  | 100.0                                                                                       | %
|Intercontinental Owner, LLC             |  | Delaware                            |  | 71.2                                                                                        | %

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