Liquid composite molding, based on resin transfer molding (RTM), vacuum-assisted resin transfer molding, and its variants, have been increasingly used in new composite material developments for both land and air military vehicle applications. New processes have high risks in cost, time, quality, and reproducibility depending on their stage of maturity. Various defense initiatives have identified physical process modeling and simulations as a viable technology to provide the required technical base to promote composite affordability and provide for process maturation. The COmposite Manufacturing PrOcess Simulation Environment (COMPOSE) was developed to model the RTM process. COMPOSE utilizes parallel processing methods on massively parallel machines so that large complicated geometries and models can be analyzed. The object-oriented design methods used in COMPOSE allow code reuse and faster software development cycles.