Exhibit 21.1

Subsidiaries of the Registrant

ARKA Group, L.P., a Delaware limited partnership

CACI-Athena, LLC, a Delaware limited liability company

CACI Azure Summit Technology, LLC, a Delaware limited liability company

CACI-CMS Information Systems, LLC, a Virginia limited liability company

CACI Dynamic Systems, LLC, a Virginia limited liability company

CACI Enterprise Solutions, LLC, a Delaware limited liability company

CACI, INC. – FEDERAL, a Delaware corporation

CACI-ISS, LLC, a Delaware limited liability company

CACI Limited, a United Kingdom private company limited by shares

CACI, LLC – COMMERCIAL, a Delaware limited liability company

CACI NSS, LLC, a Delaware limited liability company

CACI B.V., a Netherlands private limited liability company

CACI Premier Technology, LLC, a Delaware limited liability company

CACI Products Company, a Delaware corporation

CACI Technologies, LLC, a Virginia limited liability company (also does business as “CACI Productions Group”)

CACI TechWorx, Inc., a Delaware corporation

CACI-WGI, LLC, a Delaware limited liability company (also does business as “The Wexford Group International”)

CACI LGS Innovations LLC, a Delaware limited liability company

Six3 Advanced Systems, Inc., a Virginia corporation

Six3 Enterprise Systems, LLC, a Delaware limited liability company