This proposal describes research to develop an object oriented simulation system using RESQUE as its foundation, and to integrate the simulation system with a knowledge based expert system for construction process planning. RESQUE is a simulation system specifically designed to model complex resource interactions in construction processes. However, its resource representation is limited and model definition is input-intensive. The new integrated knowledge based expert simulation system extends RESQUE's modeling methodology into the object oriented paradigm where resources and operations are "encapsulated" units - each with its own knowledge, such as resource properties and interaction rules. Therefore, model definition will only involve selecting operations and resources from the system's construction processing knowledge base. With the built- in processing knowledge, the system will also be capable of giving advice on process design and process performance analysis. The formalization of process knowledge will contribute to construction basic research, and the proposed system will broaden and simplify construction simulation.