We propose to continue years 21-25 of a brain imaging and drug abuse postdoctoral T32 training program. We support this training via a variety of brain imaging tools that have yielded valuable insights into addictive disorders and related cognition. The need for such a dedicated program is driven by the emergence of innovative imaging techniques to evaluate both the anatomical and functional aspects of the brain under a variety of conditions related to substance use including acute intoxicating effects, cue-induced craving, cognitive effects, persistent neurological and cognitive defects, withdrawal, sleep disturbances, medication compliance, treatment progress and medications development. Because the nature and spectrum of the disciplines involved in imaging are broad and complex, a new breed of scientists with experience in imaging technology, multimodal analyses, neuroscience, pharmacology, addiction medicine and treatment is needed to more fully explore the neurobiological bases of drug abuse and fill the anticipated needs in the United States—our Training Program has been filling this void. Over the past 19 years we have successfully directed an integrated, multidisciplinary Drug Abuse and Brain Imaging Training Program that is supported by the outstanding environments offered by McLean Hospital/Harvard Medical School and by the Martinos Center for Biomedical Imaging at the MGH. We have trained 26 scientists over this period and all but one remains in the field. Our program emphasizes both clinical and translational research career development paths that have solid foundations in magnetic resonance [imaging, functional and spectroscopy], EEG, PET and Near Infrared Spectroscopy (NIRS). The training program infrastructure is built around two Siemens 3T clinical scanners (Prisma and new Trio upgrade to Prisma), a Varian 4T clinical scanner, a 9.4T small bore animal scanner, low- and high-density EEG/ERP and an Imagent NIRS system. Animal and clinical PET as well as 7T MRI are available at the Martinos Center. Our program also supports the hardware and offers training in how to analyze big data including working with datasets from the Human Connectome Project (HCP) and the Adolescent Brain Cognitive Development (ABCD) program. Our mentors are well funded by NIDA, NIAAA, and NIMH and so offer a unique breadth of research opportunities for our trainees. The program is designed to provide 2-3 years of training on the basics of imaging techniques as well as fundamental elements of drug abuse and psychiatry, followed by placement in one of four research tracks tailored to each trainee’s specific career goals: 1) Technology and Instrumentation; 2) Basic-Clinical; 3) Clinical/Treatment; and 4) Translational. The combination of didactic training in brain imaging and psychopharmacology with practical applications in a variety of highly successful research laboratories provide s our trainees with the skills to utilize a broad range of brain imaging techni...