Collaborative engineering design requires multiple people working together to achieve a common goal. Data sharing approach and workflow management approach have been developed to support collaborative design, but the disconnection of these two approaches has led to problems of efficiency and adaptability. In this paper, we propose a work structure based approach for collaborative design. Our goal is to improve process efficiency and adaptability by integrating management processes with engineering details and allowing designers to make certain managerial decisions through peer coordination. For a specific task, a work structure is a network of engineering work items connected by dynamically acquired engineering dependencies. It is used to generate multiple processes from which the one that best fits the current situation is dynamically determined through coordination among team participants. In order to capture engineering dependencies and associate engineering details, an adaptive work process model is developed that explicitly represents engineering work, work structure, and processes. Based on this model, a set of operations and algorithms are developed for intelligent agents to provide coordination support. Experiments have shown that by following this approach, engineering design processes can dynamically adapt to both requirement and resource changes, and the process efficiency can be significantly improved.