Abstract : This report describes an effort to develop a system designers guidebook for designing reliable distributed command and control systems. The guidebook contains a synthesis of reliable system design principles and methods to evaluate distributed system designs for performance, reliability and functional correctness. The approach to developing the system designers guidebook in this effort is example driver. We develop a detailed design of a reliable distributed operating system and evaluate its performance. Keywords: Computer architecture, Kernels, Fault tolerant systems, Reliability electronics, Zeus operating system.