In this paper we introduce a new conservative and non blocking algorithm for discrete event simulation on parallel computers with distributed memory. The new approach, called critical process first (CPF) algorithm, is especially well suited for simulating complex VLSI designs consisting of many logical processes. The algorithm avoids deadlocks by repeatedly sending lookahead information about critical processes to other computation nodes. Processes are called critical if they may directly influence processes of another computation node. To hide the communication latency of the parallel computer the CPF method gives priority to the execution of events which may affect critical processes. Simulation results show the superiority of the CPF algorithm over approaches without priority handling.