Companion Data Services (CDS) is focused on providing information technology services to the Centers for Medicare & Medicaid Services (CMS). From its Columbia, S.C., headquarters, CDS, a wholly owned subsidiary of BlueCross BlueShield of South Carolina, and the corporate Information Systems Division provide state-of-the-art healthcare insurance application systems and one of the largest healthcare insurance data centers in the world in support of Medicare, Medicaid, TRICARE, the Federal Employee Program and Medicare Advantage health plans, as well as other private health plans.