Computer systems that model new products can be overwhelmingly complex. The design of an automobile door, for example, can require the coordinated efforts of dozens (if not hundreds) of designers, engineers, and suppliers, each working simultaneously in distant locations and on radically different platforms. Project DOME integrates these efforts in a user-friendly Web-based environment that allows all developers to join in the modeling process at the same time. They can do this (1) without intermediary assistance from computer programmers, (2) without departing from their preferred set of product development tools, and (3) without losing control of proprietary information.