EXHIBIT 21 SUBSIDIARIES OF DYNACARE MARCH 12, 2001 A/ CANADIAN OPERATIONS(1): Dynacare Gamma Institutional Laboratory Services Limited Dynacare-Gamma Laboratory Partnership Dynacare Kasper Medical Laboratories Dynacare Kasper Medical Laboratories (Northern Alberta) Inc. Dynacare G.P. Inc. Dynacare International Inc. Dynacare Laboratories Limited Partnership Dynacare Realty Inc. Dynacare X-ray Services Limited ExecMed Health Services Inc. The Dynacare Health Group Inc. Ultra-Med Development Inc. GDML Leaseco Inc. Gamma-Dynacare Leasing Corporation 896988 Ontario Limited 3033331 Nova Scotia Company B/ US OPERATIONS(1) Dynacare Laboratories Inc. Dynacare Laboratory Management Inc. Dynacare Laboratories Investments Inc. Dynacare Northwest Inc. SVL Inc. Dynacare Mississippi Inc. Dynacare Southwest Laboratories Inc. (Delaware) Dynacare Texas LP, Inc. Dynacare Texas Shareholder, Inc. Clinical Laboratories Cheyenne Dynacare Texas Laboratories, Inc. HHD GenPar, Inc. HH/DL, L.P. DL/ELLIS, L.L.C. United/Dynacare L.L.C. Dynacare Louisiana Inc. Dynacare Louisiana, L.L.C. HT/DL LP SW/DL LP DL/UHS Inc. LabSouth, Inc. Dynacare Financing G.P. Dynacare Delaware Financing LLC UHS/DL, L.P. Dynacare/WPAHS L.L.C. - ------------------------- (1) Excludes legal entities with inactive business operations