The Division of AIDS supports the development and conduct of all phases of clinical trials to assess the safety and efficacy of new and improved therapies for HIV and its associated illnesses. The purpose of this contract is to provide a comprehensive quality assurance program to DAIDS-supported laboratories and collaborative institutions conducting immunophenotyping assays on patient samples. In order to provide the level of quality assurance required, the Contractor will: 1) develop and implement standards of performance for existing and newly developed immunophenotyping and immune function assays, including, but not limited to flow cytometric techniques, enzyme immune assays (EIA), cellular and serologic assays; 2) facilitate the development, evaluation and clinical application of immunophenotypic and analytical methodologies; 3) acquire, characterize, store, document and disburse quality control materials and reagents; 4) disseminate Quality Assurance technical and scientific data; and, 5) maintain a computerized system that supports the Quality Assurance Program.