This contract is for the recompetition of chemistry support services for the National Toxicology Program (NTP) Environmental Toxicology Branch (ETB). The ETB has responsibility for the Two-Year Bioassay, Short-Term Toxicology, Developmental Toxicology, Reproductive, Developmental and General Toxicology Screen, Reproductive Assessment by Continuous Breeding Immunology, and Neurotoxicology programs for the NTP, and the AIDS Therapeutics program. Chemistry support services will be needed for each program, and for program related in-house research efforts. The ETB conducts applied research with various chemicals and other potentially hazardous agents to improve test protocols, to develop new tests, and to improve interpretation of test results for the two-year bioassay program, short term toxicology program and toxicity to the reproductive, immune, and neurological systems. To insure that the species under study are exposed to the prescribed chemicals and at the specified dose concentrations, proper chemistry support is required. The necessary support includes chemical characterization, dose preparation, dose concentration verification, and internal dose determination. These contracts will provide chemistry support services which are to include bulk chemical procurement, bulk chemical handling, preliminary chemical studies, bulk chemical comprehensive analyses, limited bulk chemical analyses, bulk chemical inhalation analyses, dose formulation developmental studies, dose preparation analysis, dose analysis, referee analysis, dose vehicle analysis, chemical storage, shipment, hazardous waste disposal, biological sample method development, toxicokinetic study, biological sample analysis, and prestart toxicokinetic study. Additional requirements include providing a quality program, safety and health, animal care, disposal of wastes, computerized project management system, coordination with other NTP contractors, microfiching data, and providing continuity of services.