Due to ever increasing competitive market place, demanding customers, and rapidly advancing technologies, corporations developing new products are forced to look into all the possible areas of improvement throughout the entire product lifecycle management process. One of the research areas that have been overlooked in the past is Engineering Change Management (ECM). This paper presents a simulation model for investigating the mutual impacts of ECM process and New Product Development (NPD) process on each other. The discrete-event simulation model incorporates ECM into an NPD environment by allowing Engineering Change (EC) activities to compete for limited resources against regular NPD activities. The goal of the research is to determine the key characteristics of ECM and NPD that affect lead time and productivity of both processes. Decisions to be made by considering EC impacts are drawn from an enterprise level systems perspective.