EXHIBIT 21.  PARENT AND SUBSIDIARIES OF REGISTRANT

The  subsidiaries  of MART are listed  below.  All are engaged in the  ownership
and/or  development  of  commercial  real estate in the United  States.  All are
included in the consolidated  financial  statements filed as part of this Annual
Report.
                                             State of Incorporation
Name                                              or Formation         Interest
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CORPORATIONS:
BTR Arkor, Inc.                                      Maryland             100%
BTR Atlanta Daycare, Inc.                            Maryland             100%
BTR Business Center, Inc.                            Maryland             100%
BTR East Greenbush, Inc.                             Maryland             100%
BTR Fallston Corner, Inc.                            Maryland             100%
BTR Free State Bowls, Inc.                           Maryland             100%
BTR Gateway, Inc.                                    Maryland             100%
BTR Holdings, Inc.                                   Maryland             100%
BTR Manassas, Inc.                                   Maryland             100%
BTR Marigot, Inc.                                    Maryland             100%
BTR Marina, Inc.                                     Maryland             100%
BTR New Ridge, Inc.                                  Maryland             100%
BTR Northwood Properties, Inc.                       Maryland             100%
BTR Odenton Properties, Inc.                         Maryland             100%
BTR Ray Road, Inc.                                   Maryland             100%
BTR Salisbury, Inc.                                  Maryland             100%
BTR Southdale, Inc.                                  Maryland             100%
BTR Union Hills, Inc.                                Maryland             100%
BTR Waldorf Development Corporation                  Maryland             100%
BTR Waldorf Tire, Inc.                               Maryland             100%
Burke Town Plaza, Inc.                               Maryland             100%
Brandywine Commons, Inc.                             Maryland             100%
Clinton Development Company, Inc.                    Maryland             100%
Colonie Plaza, Inc.                                  Maryland             100%
Columbia Plaza, Inc.                                 Maryland             100%
Commonwealth Plaza, Inc.                             Maryland             100%
Concourse Realty Management, Inc.                    Maryland             100%
Davis Ford Properties, Inc.                          Maryland             100%
Essanwy, Inc.                                        Maryland             100%
Easton Shoppes, Inc.                                 Maryland             100%
Fredericksburg Plaza, Inc.                           Maryland             100%
Harrisonburg Plaza, Inc.                             Maryland             100%
Kingston Crossing, Inc.                              Maryland             100%
MART Acquisition, Inc.                               Maryland             100%
New Town Village, Inc.                               Maryland             100%
North East Station, Inc.                             Maryland             100%
Orchard Landing Apartments, Inc.                     Maryland             100%
Orchard Landing Limited, Inc.                        Maryland             100%
Rolling Road Plaza, Inc.                             Maryland             100%
Rosedale Partners, Inc.                              Maryland             100%
Rosedale Plaza, Inc.                                 Maryland             100%
Route 642 Properties, Inc.                           Maryland             100%
Southdale Mortgage, Inc.                             Maryland             100%
Southwest Development Properties, Inc.               Maryland             100%
Timonium Shopping Center, Inc.                       Maryland             100%
Wake Plaza, Inc                                      Maryland             100%
Waverly Woods Center, Inc.                           Maryland             100%
Wyaness, Inc.                                        Maryland             100%


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LIMITED LIABILITY COMPANIES:
Perry Hall Square, LLC                               Maryland             100%
Pittsfield Center, LLC                               Maryland             100%
Radcliffe, LLC                                       Maryland             100%
Round Hollow, LLC                                    Maryland             100%
Stonehenge, LLC                                      Maryland             100%
Talton, LLC                                          Maryland             100%
Timonium Shopping Center Associates, LLC             Maryland             100%
Yorkway Associates, LLC                              Maryland             100%


         The following are partnerships in which  Mid-Atlantic  Realty Trust has
partnership interests:


                                                      State of
Name                                                  Formation        Interest
--------------------------------------------------------------------------------
Kensington Associates                                 Maryland            93%
MART Limited Partnership                              Maryland            82%
Northwood Limited Partnership                         Maryland            67%
Ritchie Limited Liability Partnership                 Maryland            67%
Rosedale Plaza Limited Partnership                    Maryland           100%
Saucon Valley Limited Partnership                     Maryland            89%
Scotia Associates Limited Partnership                 Maryland            50%
Southdale Limited Partnership                         Maryland            50%
Wyaness Associates                                    Maryland           100%


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