This award to James Bower will support continued development and distribution of A General Neural Simulation System (GENESIS) for Computational Neurobiology. The specific extensions and further development include the release of a new version of the software, continued efforts to develop versions of the package on parallel machines, continued documentation, development of an interface between GENESIS and the simulator NEURON, and the extension of the development of simulator performance measures to network. In addition, this award will allow new collaborations with the Pittsburgh Supercomputing Center and the Scientific Visualization Laboratory at the University of Illinois Chicago. This package will be used by both the research and the educational communities. The award is being supported by the Computational Neuroscience Program, the Numeric, Symbolic, and Geometric Computation Program, and the Computational Biology Program.