This research is a Cooperative effort between Professor George J. Cokkinides/ University of Sout Carolina at Columiba//ECS-8715364 and Professor A. P. Melipoulos of Ga Tech Research Corp./ECS-8715364, and is focused on the formulation of a methodology probabilistic simulation of the compsite (generation plus transmission) power system. The formulation is based on a probabilistic representation of the electric load, customer-owned generation availability, transmission availability, etc. Major operating practices such as economic dispatch together with pertinent system constraints such as random forced outages are included the aim of the work is new reliability and transmission loss evaluation techniques currently not available.