This presentation will examine the leadership of powerful product development managers and their impact on supplier involvement, customer involvement, and concurrent engineering. Using responses from 406 product development managers and executives in the U.S. and German auto industries, this research validates a model of powerful product development managers and their influence on internal and external integration. The results indicate that powerful American product development managers have significant positive relationships with both internal forces and external forces in order to develop marketable products well. In contrast, German managers have significant positive relationships only with internal forces and weak relationships with external collaborators, such as suppliers and customers.