We propose to continue a Jointly Sponsored Predoctoral Training Program in Neurosciences that is the major source of support for early year students in the Ph.D. Program in Neurosciences at Harvard University. The goals of this interdepartmental Ph.D. program, established in 1981, are (1) to organize the neuroscientists at Harvard Medical School, its affiliated hospitals, and Harvard College into a single training faculty cohort; and (2) to train research scientists and teachers who are interested in mental health, diseases of the nervous system, and fundamental mechanisms of the brain. The training program is designed to provide talented trainees with a broad and thorough background in neuroscience and to mentor them in performing original and rigorous research in important areas of neuroscience. During the first year, students are provided with initial preparation in quantitative approaches to scientific endeavors. This is followed by a year long course, The Discipline of Neuroscience, which provides integrated and rigorous training in concepts central to our understanding of the development, function, and diseases of the nervous system at the levels of cellular signaling, circuit computations, and behavior generation. All students take an additional course in Statistical Approaches to Neuroscience, a neuroanatomy course and two electives. Students also rotate through three different laboratories during the first year. Following the coursework, laboratory rotations, and a preliminary examination, students begin full time, mentored dissertation research. During the program, students are also involved in other ongoing training activities including journal clubs, seminars, retreats, skill workshops, and data presentation. There are currently 102 graduate students enrolled in the Program in Neuroscience; this grant supports 14 students in the first or second year of graduate education. There are 141 faculty in the Program in Neuroscience; the 74 faculty who are currently most actively involved in graduate education are training mentors on this proposal. Considerable effort has gone into making this program a highly interactive group with extensive formal and informal contacts between students and faculty. Graduates of this program go on to distinguished careers in biomedical research and make substantial contributions to a growing understanding of neuroscience.