The long range goal of this program is the development and commercialization of proton accelerators suitable for radiation therapy of cancer in hospital or clinical settings. These can provide beams of protons up to 60 nA at 250 MeV in a smaller version of the accelerator. A larger version will produce helium ions to 250 MeVmu, or with lower magnetic field, 250 MeV protons form H- acceleration and charge exchange extraction for precision current control. The later could make the use of raster scanning beams of protons for dose delivery to the patient possible, with significant implications in reducing the size and cost of the gantry and the potential for significantly improved radiation treatment. The Phase I effort completed the conceptual design and cost estimate for these accelerators. The Phase II program would construct models of the magnets designed, assemble them in a section of a ring, and conduct a series of experimental demonstrations with H- beam injected from a 300 KeV preaccelerator, including simulated charge exchange extraction with feedback current control. These would demonstrate the commercial feasibility of the design concepts. Phase III, supported privately, would make commercial units available.