With the U.S. experimental effort in high energy physics (HEP) largely dependent on the operation of highly specialized accelerators, the understanding and prediction of the performance of these accelerators becomes critical to the overall success of the DOE HEP program. A specific newly identified problem lies in the simulation and optimization of Fixed Field Alternating Gradient (FFAG) machines and related devices, for which currently available tools provide only approximate and inefficient simulation. This project will develop a set of tools that can describe the complex specific electromagnetic fields ¿ including high-order fringe fields, edge effects, and general field profiles ¿ and can accommodate the large emittance of the beam necessary for accurate predictions of dynamic aperture. In order to simplify design needs, modern global, non-local optimization techniques will be connected to the tools to allow efficient probing of the (usually) very high dimensional parameter space. User-friendly interfaces also will be developed to enhance the audience and lessen the expertise typically required in the use of accelerator codes. Commercial Applications and other Benefits as described by the awardeeThe development of broad, highly-accurate accelerator models with powerful optimization tools and user-friendly interfaces not only would aid in the development of new accelerators but also would promote the transfer of accelerator technology into commercial and medical applications, such as hadrontherapy, neutron and light sources, and other potential markets for accelerators