An electron-beam mask-generation system designed to demonstrate fast turn around and high resolution capability is described. The system has been developed using an Advanced Metals Research 900 SEM and a Nuclear Data 812 computer. Patterns are generated utilizing a matrix of4096×4096randomly addressable data points. Complex and/or large patterns can be generated by mechanical repositioning of the substrate and scanning of adjacent fields. A complete stepped and repeated master plate is produced in several hours as compared with several days using conventional systems. The time saving has been primarily achieved by combining the artwork generation, reduction, and step and repeat operations into a single operation. Compatibiltiy with conventional computer aided design and graphics software has been maintained by translating ordinary artwork generation data into information acceptable by the electron-beam system. Extensive software allows virtually all geometries to be generated by the system.