Building on the record of excellence in training physician-scientists, the present application seeks to improve upon the existing neonatology postdoctoral training program at the University of Iowa by enhancing the investigators' strengths and expanding the investigators' capabilities. The investigators' objective is to provide three M.D. or M.D./Ph.D. trainees with 2 to 3 years of rigorous, high caliber, state-of-the-art training in medical research. The acquisition of the requisite knowledge, skills, and work habits by the investigators' trainees will take place in a nurturing environment emphasizing scientific excellence and collaborative teamwork. The program's faculty preceptors include senior and mid-level scientists who have established successful careers as medical researchers and mentors. The faculty includes a spectrum of researchers from the departments of basic science (Biochemistry, Anatomy & Cell Biology, Physiology and Biophysics) and from clinical medicine (Pediatrics, Internal Medicine, Obstetrics and Gynecology, and Otolaryngology). Institutional resources available to trainees are outstanding. The selection of trainees is competitively based on their potential for becoming independent physician-scientists capable of assuming leadership roles in research and clinical medicine. After selecting a faculty preceptor and an area of research, trainees will pursue hypothesis-based research in one of the five research areas of the preceptor faculty's strengths: developmental physiology, developmental biology, gene therapy, molecular genetics, and clinical trials/epidemiology. Because of the overlapping and collaborative research interests among the faculty, trainees will have multiple opportunities to interact with a diverse spectrum of faculty. Each trainee's research program will be developed on an individual basis with input and guidance from the trainee's preceptor, the Program Directors, and the Neonatology preceptor faculty. In addition to engaging in hands-on laboratory experiences, trainees will learn directly about the nature of high quality scientific research by attending research seminars, lectures, and laboratory meetings, by writing research proposals, manuscripts, and grants, and by participating in research conferences. Other important elements are group support and mentoring by the neonatology faculty with input from and oversight by the proposed Program and Internal Advisory Committees. Proposed program's effectiveness will be prospectively evaluated in a systematic fashion. With NIH support beyond that which the investigators currently enjoy, the investigators will be able to significantly enhance the research training experiences they offer their postdoctoral physician trainees in neonatal medicine.