Given the growing burden of substance use and rapid shifts in how we study substance use (SU) and substance use disorders (SUDs), there is a critical need for a well-trained and diverse workforce to conduct impactful research on SU and the complexity of its consequences. Responding to this need, we propose renewal of the Drug Dependence Epidemiology Training (DDET) program at Johns Hopkins Bloomberg School of Health (JHBSPH). DDET has provided research training for >29 years and has produced many of the nation’s leading SU researchers. We benefit from strong institutional support for training, comprehensive course offerings in epidemiology and statistics, and research in SU at JHBSPH and across Johns Hopkins University. Recent accomplishments have been exceptional, indicating that DDET continues to make a tremendous impact on the field. Among those who completed training in the current project period, all predoctorates completed their doctoral degrees in 4 years; all trainees (both pre- and postdoctoral) continued in research careers; and 8 (of 13) postdoctorates are in faculty positions. The DDET team includes two co-directors (Maher, Johnson), five associate directors (Sherman, Latkin, Mojtabai, Linton, Thrul), and 33 additional faculty (9 core, 24 affiliate). The participating faculty have sub- stantial research expertise in substance use and SUDs, and all will work together to implement the training plan and provide trainees with opportunities to engage in supervised research. The DDET program has strong and stable leadership, highly-qualified faculty, clear and relevant program goals, and an ongoing record of excellence. Our mission is to create the next generation of scientists who will tackle the challenges of substance use, SUDs, and their related harms. Our 5-year goals are to train scholars who will: [1] investigate the causes and consequences of substance use and SUDs; [2] respond to gaps in treatment and services for SUDs; and [3] develop, implement, evaluate, and scale-up interventions to address substance use, SUDs, and their related harms. DDET is designed to provide broad knowledge in the fundamentals of research in substance use epidemiology, services, and prevention, as well as specialized training in one or more of the focal areas. With this competing renewal, we propose to provide cross-disciplinary, specialized research training in drug use for 7 pre- and 7 post-doctoral scholars. We have identified 5 focal areas that will enhance the quality and relevance of training, each is led by an associate director. Focal areas include: [1] harm reduction & overdose prevention; [2] interventions for SUD & infectious disease; [3] SUD & psychiatric comorbidities; [4] structural determinants & drug control; and [5] emerging trends & technologies. Cross-cutting training areas include polysubstance use, health equity, and human dignity. Training activities include coursework, seminars and webinars, research apprenticeships, participatio...