Abstract: Parallel system techniques can improve the effectiveness and correctness of decision making, especially in complex circumstances. By analyzing the requirements of parallel systems for decision making support, the requirements of simulation environment for parallel systems, and the requirements of constructing simulation environment, technical challenges for constructing parallel systems are formulated. Furthermore, the Domain Simulation Engineering is employed to slove some of these aforementioned challenges. Finally, in order to reduce the diculty to realize “Simplicity and Consistency” when modelling agents in parallel systems, techniques such as component-based modelling of entity models, centralized modelling of intelligent components, and plug-in-based behavior modelling of agents are explored.