This proposal requests continued support for the Medical Scientist Training Program (MSTP) at Vanderbilt University. The primary goal of the Vanderbilt MSTP is to identify, mentor, and foster the careers of future leaders in academic medicine who are dedicated to improving human health through research. The program is based on rigorous training in clinical medicine and scientific inquiry. Successful completion of the MSTP leads to both M.D. and Ph.D. degrees. Core elements of the program developed specifically for dual-degree students include a literature-based seminar series, clinical preceptorship program, data club, leadership workshop, career development workshop, physician-scientist speaker series, and an annual retreat. Formal instruction in responsible conduct of research is provided throughout the curriculum. An innovative advising college program offers opportunities for student advising by faculty members and senior trainees. The MSTP supports students enrolled at both Vanderbilt University and Meharry Medical College. Seventy-four percent of our graduates with established careers hold academic or private-sector research positions, including two deans and 20 full professors. More recent graduates still in training have been placed in superb residencies and fellowships. The 84 current trainees come from 59 colleges and universities distributed across North America. The nationwide applicant pool results from concerted recruiting efforts, including those focused on the recruitment of students from groups underrepresented in medicine. In the current year, 275 applications have been received, from which 12 students will be selected to enter the incoming class. The proposed goal is to increase the size of the program to a steady state of 96 students over the next five years. The educational environment for physician-scientists at Vanderbilt University is outstanding. Extramural research funding has increased from $256 million to $389 million since 2003. Building on established strengths in cancer biology, cell biology, clinical pharmacology, diabetes, signal transduction, toxicology, and vaccine science, new areas of research emphasis include biomedical informatics, chemical and physical biology, genetics, imaging sciences, neurosciences, and structural biology. The proposal requests an increase in funded positions to 32 (29 for Vanderbilt; 3 for Meharry) during the five-year project period. Ongoing support for the Vanderbilt MSTP is based on the strength of the applicant pool, enhanced opportunities for physician-scientist training, and an institutional commitment to the education of leaders in biomedical research. The Vanderbilt Medical Scientist Training Program supports the training of physician-scientists who seek to improve human health through basic, translational, or clinical research. The broad public health significance of this program will be realized through the academic and scholarly accomplishments of the trainees, with connections to both the direct treatment of patients in the clinical setting and the discovery of basic disease mechanisms and new therapeutic agents.