The Division of Pharmacotherapies and Medical Consequences of Drug Abuse (DPMCDA) of NIDA supports research and development of new medications for the treatment of drug addictions. A critical aspect of this development involves studies on the metabolism, pharmacokinetics and clinical pharmacology of new medications. Biological specimens from these studies require quantitative determination of the study medication and its metabolites and the abused substances by highly sensitive and specific methodology. The purpose of this contract is to support the Institute's efforts in these areas by providing a centralized analytical facility capable of carrying out analyses on a wide variety of compounds, e.g., illicit drugs, potential medications and their metabolites, as well as endogenous substances, in biological fluids in support of medications development.