Project Summary/Abstract The Pediatric Emergency Medicine Research Training Program (PEMRTP), established in 2001, offers unique multi-disciplinary training for MD and PhD biomedical researchers to acquire necessary skills for investigating the acute illnesses and injuries that form the clinical basis of the subspecialty of pediatric emergency medicine. In the United States, between 19 and 25 million children make more than 29 million emergency department (ED) visits each year. Eighteen percent of children have at least one ED visit annually. About 4% of these visits result in hospitalizations. The total annual cost of ED care is almost $50 billion and 20% of visits are for children. When arriving at the ED, a parent can think of nothing more important than that their acutely ill or injured child receive the best, evidence-based care with the most effective diagnostics and treatments. Pediatric research makes this possible. The NIH recognizes the importance of emergency medicine research and has recently designated a trans-NIH Office of Emergency Care Research to foster basic, translational, and clinical research and training for the emergency setting. This T32 competing renewal leverages the assets of Boston Children’s Hospital Emergency Department, which includes the largest pediatric emergency medicine faculty, and leading informatics programs at Harvard. PEMRTP draws on core strengths to create a culture of rigorous research and research training to (1) prepare individual trainees as independent researchers, (2) fill the critical need for early and mid-career research mentors for the next generation of pediatric emergency medicine trainees here and elsewhere, and (3) bolster pediatric emergency medicine research with biomedical informatics and genomics. Trainees progress toward independence in three interrelated phases: (1) a mentored research project, (2) formal course work, and (3) preparation of a research grant. Trainees complete either a Master of Medical Science or Master of Public Health degree. They are mentored in their laboratory of choice. And finally, with guidance from a faculty mentor, they prepare a K99/R00 or similar mentored research grant application to facilitate their transition to independent faculty. Boston Children’s Hospital and Harvard Medical School, by the breadth and depth of their research laboratories, operational, real-world clinical systems, formal academic programs, experienced faculty, and linkages to multisite research networks, provide an unparalleled environment for mentoring trainees to become future leaders. PEMRTP specifically builds on the international reputation of Boston Children’s Hospital in biomedical informatics and genomics and seeks to train its fellows to use tools from these fields to exploit the pediatric ED as a laboratory for clinical, translational and population research.