Laboratory Corporation of America Holdings is a healthcare diagnostics company. The Company, together with its subsidiaries, is engaged in providing clinical laboratory services and drug development support. The Company operates through two segments: LabCorp Diagnostics (LCD) and Covance Drug Development (CDD). The Company's LCD segment is an independent clinical laboratory business that consists of a network of approximately 40 primary laboratories and approximately 1,700 patient service centers (PSCs) along with a network of branches and STAT laboratories, which offer a menu of routine and frequently ordered tests. LCD offers a menu of over 4,700 tests, such as blood chemistry analyses, urinalyses, blood cell counts and thyroid tests. Its CDD segment offers drug development services, and provides a range of drug development solutions across the world, primarily to companies in the pharmaceutical and biotechnology industries.