The GRASP system promotes recovery of hand function following stroke through an instrumented orthosis that enables functional practice of manual tasks in fun and engaging activities within a virtual environment. The effort combines patented sensor glove technology developed under the NASA space suit program with a commercial hand orthosis and modern game engine technology. Barron Associates has successfully completed design, fabrication, integration, and testing of a fully functional prototype system. A pilot study is currently underway to investigate the primary Phase I hypothesis, which states that GRASP-generated metrics during practice of virtual activities will correlate significantly with accepted measures of hand function for stroke patients with hemiparesis. Additionally, two home use case studies are being conducted to explore usability in the home environment and serve as pathfinders for Phase II efficacy trials.