Abstract. WARP3d(1,2), a threedimensional PIC/acceleratorcode, has been developed over several years and has played a majorrole in the desi~n and analysis of space-chargedominated beam experiments being carriedout by the heavy-ion fusion programsat LLNL and LBNL. Major fatures of the code will be reviewed, including: residence corrections which allow lqge timesteps to be taken, electrostatic field solution with subgridscale resolution of internal conductor boundaries, and a bent beam atgorithm. Emphasis will be placed on new features and capabilities of the code, which inclu&: a port to parallelprocessing environments, spaceeharge limited injection, and the linking of runs covering different sections of an aeederator. Representative applications in which the new features and capabilities are used will be presented along with the importantresults..