Exhibit 21 Aberdeen Technical Services LLC Advanced Repair Technology International Ltd AdvanceMed Corporation AT/Mexico Holdings Inc. AT Professional Services Corporation Dyn Funding Corporation Dyn Marine Services, Inc. Dyn Marine Services of Virginia, Inc. Dyn/Mexico Holdings Inc. Dyn Network Management, Inc. Dyn Realty Corporation Dyn Systems Technology, Inc. Dyn Technical Services, Inc. Dyn Trade Systems, Inc. DynCIS, Inc. DynComm 2000 LLC DynCorp Advanced Repair Technology, Inc. DynCorp Aerospace Operations Inc. DynCorp Aerospace Operations (UK) Ltd. DynCorp Aviation Services, Inc. DynCorp Biotechnology and Health Services, Inc. DynCorp de Honduras S. De R.L. DynCorp Information & Enterprise Technology, Inc. DynCorp Information Systems LLC DynCorp International LLC DynCorp International Services GmbH DynCorp International Services, Inc. DynCorp International Services Ltd. DynCorp International Services Ltd. DynCorp Management Resources, Inc. DynCorp Management Resources LLC DynCorp of Colorado, Inc. DynCorp Panama, Inc. DynCorp Procurement Systems, Inc. DynCorp Property Management, Inc. DynCorpServices.com, Inc. DynCorp Technical Services LLC DynCorp TechServ LLC DynCorp Tri-Cities Services, Inc. DynCorp Viar Inc. DynEDRS, Inc. DynEx, Inc. DynKePRO LLC DynMcDermott Petroleum Operations Company DynMeridian Corporation DynPar L.L.C. DynPort Vaccine Company LLC DynSpace Corporation DynTel Corporation Grupo DynCorp de Mexico S.A. de C.V. Healthcare Integrity Services LLC New Mexico Technology Group LLC Western Ranges LLC