This training grant will continue to provide support for graduate student studying in the area of molecular biophysics. The support provided through this mechanism serves to encourage students entering the University of California at Berkeley to choose biophysics/structural biology as their area of specialization for graduate study, and to increase the options for them. It also provides resources for the Structural Biology Seminar program, bringing in prominent workers in this field to present their work and meet with students and faculty. The students take a small number of core courses, which are centered, in contemporary problem in molecular biophysics, and the methods for analysis of such systems. These are complemented with other courses to fill in background and strengthen understanding in both systems of interest and their context in the complex cellular environment. Research projects span many areas including: determining three dimensional structures of proteins and nucleic acids in 3D crystals, 2D crystals, membranes and in solution; determining mechanism of enzyme catalysis and the relationship of protein dynamics to catalysis; the higher order structure of DNA in cells and how it is maintained and regulated; the folding of complex RNAs, and RNA protein interactions; the structure of biological membranes and how they influence cell-cell interactions; the folding pathways of proteins and the basis for protein stability; theoretical methods for understanding protein folding and networks of interacting proteins in cells; the use of mass spectroscopy and other methods for proteomics. For trainees who are entering graduate students the first year program includes rotations and selection of a research director, starting research work, doing course work, training as an instructor (teaching assistant), and attending seminars, particularly the weekly Structural Biology Seminar. In the second year research becomes a major focus, although coursework and teaching continue, as does attending seminars. For trainees who are supported later in their graduate stay a majority of time is spent in research, but regular attendance at seminars is expected. Courses in the fast two years include core courses in MCB and Chemistry on systems and methods for biophysical analysis, as well as background courses in fundamentals of physics, chemistry and biology selected to complement the student's undergraduate background. Special courses in techniques, such as x-ray crystallography and NMR, are offered, as are courses in specialized systems such as enzymes or nucleic acids.