This award will support researchers at three institutions, the University of California at San Diego (UCSD), the San Diego Supercomputer Center (SDSC), and The Scripps Research Institute (TSRI), to develop, distribute, and maintain software for the structural biology community. The software will involve aspects of both molecular modeling and visualization (at TSRI), development of improved methods in crystallographic refinement (UCSD), and the documentation and support of the software (at SDSC).