Summary Diabetes mellitus is an epidemic and a major cause of blindness, kidney disease, amputation and cardiovascular disease around the world. Other endocrinologic and metabolic diseases also have major implications for public health. We urgently need to train patient- and population-oriented researchers to provide an evidence base for the optimal prevention and treatment of these conditions. Researchers need methodologic training and skills in chronic disease epidemiology, clinical trials, health services delivery and implementation science to improve health equity and health outcomes. For the past 20 years, our T32-supported training program has played an essential role in training the next generation of patient- and population-oriented researchers in diabetes, endocrinology, and metabolism. Since its inception, we have successfully trained 25 pre-doctoral and 25 post- doctoral scholars, who have authored 212 peer-reviewed papers during training. Many of these former trainees now hold research positions across the country with NIH-funded research programs (see Progress Report). We have trained 12 individuals underrepresented in science and medicine and 23 women. At Johns Hopkins there is increasing breadth and depth of endocrinology and diabetes research across schools and departments, particularly with newly funded interdisciplinary programs focused on cardiometabolic health equity and diabetes management and prevention. In this next cycle we propose to unite this research training into single program to promote multidisciplinary collaboration and thereby better address the real-world challenges facing our communities. We propose to double the number of mentors from across the institution, providing diverse expertise in multiple research areas in diabetes and endocrinology, with a particular emphasis on diabetes, diabetes prevention and metabolic disease throughout the life course, health disparities and equity, and special populations disproportionately affected by diabetes and endocrine diseases (e.g., persons with mental health disorders, cystic fibrosis, and HIV). The vast research resources available at Johns Hopkins will support the training of additional fellows. We plan to recruit diverse trainees in adult and pediatric endocrinology, General Internal Medicine (post-docs) and public health or epidemiology (pre-docs) from a national pool of applicants; provide a rigorous training experience in patient-oriented and epidemiologic research in diabetes, endocrinology and metabolism; utilize existing data from well-characterized cohorts and trials to enable trainee projects to be rapidly executed; engage trainees in high caliber collaborative research to address important questions and test meaningful hypotheses under the supervision of nationally renowned, multidisciplinary faculty; integrate multi- layered mentorship for each trainee to develop scholarship and an investigative career; evaluate the outcomes of the program and make modific...