PROJECT SUMMARY Substance use disorders occur at the interface of behavior and pharmacology. This is a proposal to renew an ongoing and successful postdoctoral clinical research training program on the human behavioral pharmacology of substance abuse, for its 41st thru 45th years. Nine training positions are proposed, all at the postdoctoral level. Training duration is two to three years. The goal is to produce experts in various aspects of substance abuse, psychopharmacology, and treatment who go on to succeed as independent clinical researchers, scientists, academicians, and administrators in drug abuse and related fields. The program has a long and successful history, with many distinguished graduates. The program will provide training and experience in translational experimental clinical trials research methods, extending from the human laboratory to the clinic. Training consists primarily of conducting supervised clinical research in collaboration with training faculty and analyzing and publishing the results, conclusions and implications of that research. Trainees attend and report at major scientific meetings and participate in an organized program of educational seminars designed to provide both breadth and depth to their knowledge and skills relevant to drug abuse and clinical research. The training program site is a multifaceted drug abuse clinical research program -- the Behavioral Pharmacology Research Unit -- plus other affiliated drug abuse treatment and research programs, primarily on the same campus, but extending more broadly into the community as well. Research training is provided in the following areas: clinical pharmacology of drugs of abuse; medications development research; the cognitive neuroscience and behavioral toxicity of drugs of abuse; abuse liability assessment; pharmacological treatment of drug abuse; behavioral treatment of drug abuse, especially incentive-based strategies; integration of behavioral and pharmacological treatments; psychiatric and medical comorbidity; behavioral and neuropsychiatric assessment; HIV risk behavior assessment; promotion of engagement and adherence; and clinical trials research methods and trials management. Training includes a broad range of abused drug classes – opioids, cocaine, prescription medications, cannabis, club drugs/psychedelics, alcohol, tobacco/nicotine, and caffeine.