Project Abstract Despite decades of research in the understanding and treatment of diseases of the heart and lung, cardiovascular and pulmonary diseases remain the leading causes of hospitalization, disability, and death in the U.S. Notably, growing numbers of patients with childhood-onset chronic illnesses, such as congenital heart defects, cystic fibrosis, bronchopulmonary dysplasia, and hemophilia, are surviving into adulthood, making it imperative to conduct research encompassing the lifespan. Against this background of critical research needs, there is a strikingly growing shortage of M.D.-scientists, such that the proportion of M.D.s that remain primarily in research careers has decreased by 3-fold in the last 3 decades, despite the climbing number of total physicians in practice. The pipeline of M.D.-scientist development is also at risk: fewer medical students express interest in a research career, and fewer graduates apply for NIH funding. Importantly, relative to the overall physician workforce, women and minorities are disproportionately underrepresented in the proportion of M.D.-scientists. These challenges require the implementation of innovative recruitment and training strategies to feed the M.D.- scientist pipeline and ensure that women and minorities are well-represented. To help fill these critical gaps, we will establish the University of Texas Southwestern (UTSW) - Stimulating Access to Research in Residency (UT-StARR) training program to recruit and train a diverse group of Internal Medicine and Pediatrics residents that will become the next generation of M.D.-scientists conducting laboratory-based, translational, clinical, and population health research to detect, treat, and prognosticate diseases affecting the heart, lungs, and blood of diverse populations throughout the lifespan. Our institution will provide an ideal environment with a multidisciplinary cadre of funded research; robust didactic training program; and diverse patient population. We hypothesize that the 3 axes of diversity at UTSW - M.D. trainees, mentors, and patient community - afford the unique opportunity to address unmet needs in M.D. research training, personalized medicine, and population health. The following Aims organize our approach: Aim 1. To provide broad-based comprehensive mentored research training for a group of diverse Internal Medicine and Pediatric resident-investigators in the conception, design, and implementation of laboratory-based, translational, clinical, and population research in diseases affecting the heart, lungs and blood, encompassing detection, prevention, treatment, and outcomes to improve the health of individuals and populations throughout the human lifespan; Aim 2. To provide the essential research training and mentoring platform needed to build a strong foundation allowing successful transition of residents to independent M.D.-scientists conducting biomedical research in the heart, lung, and blood fields; Aim 3. To enhanc...