ABSTRACT. The goal of the Molecular Biophysics Training Grant (MBTG) at the University of California San Diego is to provide a rigorous and strongly interdisciplinary training program for graduate students, with the aim of training the next generation of scientific leaders striving to solve important biological problems using Molecular Biophysics approaches. To accomplish this goal, trainees with strong quantitative backgrounds and a demonstrated aptitude, commitment, and passion for research are selected at the end of their first year from a diverse group of applicants from 32 well-funded training faculty labs. The MBTG faculty are highly interdisciplinary and many have cross-campus appointments in several departments. Trainees come mostly from two graduate programs, Chem/Biochem and Biomedical Sciences but a few come from Physics, Biology and Bioengineering. During their first year, all students engage in research rotations and choose a research lab. At UCSD, students are free to rotate with any faculty across campus and to choose any faculty for their thesis advisor. First year students receive training from their respective graduate programs in critical reading of literature, exposure to important unsolved biological problems, ethics and graduate school survival skills. MBTG Trainees are appointed and choose their thesis committee at the end of their first year. All MBTG trainees take two rigorous core courses in Molecular Biophysics and will have an intensive week-long Statistics workshop. During their second year, they write and defend their thesis research proposal. Required trainee activities include a full-length seminar presentation of their research at the monthly student seminar, monthly discussions of rigor and reproducibility, a monthly journal club, a yearly retreat, career workshops and outside mentors. Trainees may apply to be reappointed for a maximum of two years of support. All trainees present their research every year at the annual retreat, with alumni trainees giving lightning talks each year until graduation. Throughout their graduate training, trainees take advantage of career development opportunities and mentorship, including yearly IDPs and group and individual engagement with outside mentors. The program emphasizes the development of creative independent thinking, strong quantitative skills with a focus on rigor and reproducibility, scientific communication, and mentoring. The MBTG provides the critical interdisciplinary “home” at UCSD for students and faculty interested in Molecular Biophysics. The high quality of student publications, postdoctoral fellowships, faculty positions, and industry positions obtained by our trainees are strong evidence of successful training outcomes. Given the depth, quality, and diversity of our student pool and our demonstrated training outcomes, we request 12 students be supported each year.