This contract will provide support for a NHP Core Quantitative Viral RNA Laboratory for the conduct, improvement, and development of assays designed to detect and characterize viral RNA in the plasma, mucosal tissues and secretions, lymphoid tissues, and other specimens from NHP that have been infected with SIV, SHIV, or HIV in studies conducted at the NIAID Simian Vaccine Evaluation Unit (SVEU) contract sites or by NIH-supported investigators.