In this renewal application, the Johns Hopkins Training Program in Sexually Transmitted Infections seeks training support for 4 pre-doctoral and one postdoctoral position annually. Trainees are supported within 3 tracks-clinical epidemiology, behavioral sciences and health policy, and 19 faculty with funded research programs are mentors, representing nearly all of the disciplines relevant to STIs. This is a multidisciplinary program, with faculty from the Departments of Epidemiology, Population and Family Sciences, International Health, from the School of Public Health, and from the Departments of Medicine/Infectious Diseases, Obstetrics-Gynecology, and Pediatrics-Adolescent Medicine from the School of Medicine. Predoctoral students are recruited through a competitive process and who have completed their initial coursework and who are developing a thesis in one of the relevant areas. Postdoctoral fellows are encouraged to pursue clinical research projects using the Baltimore City Health Department and Johns Hopkins service venues and databases. A structured didactic, mentoring and evaluation program is a key component. All trainees will be required to take (if they have not done so) prescribed courses covering the prevention and control of sexually transmitted diseases and advanced epidemiology courses. Supporting academic activities include a weekly STD seminar series, a monthly journal club and a monthly research methods workshop. Overall progress is monitored by an Executive Committee of senior faculty mentors. In the first 4 years, we have trained 10 predoctoral and 3 postdoctoral trainees, who have published 13 peer-reviewed papers. Our overall aim is to train young promising investigators to be clinical research leaders in STI control.