Workflow management, which is concerned with the coordination and control of business processes using information technology, has grown from its origins in document routing to include the automation of process logic in business process engineering. Workflow also has a strong temporal aspect. Activity sequencing, deadlines, routing conditions,and scheduling all involve the element of time. Temporal expert systems, which use knowledge-based constructs to represent and reason about time, can be used to enhance the capabilities of workflow software. This paper presents a temporal expert system workflow component for tracking engineering design changes. We use Allen's theory of temporal intervals in our model to enhance the decision-making, timing, and routing activities in a workflow application. We test the model using information from a "real-world" engineering design situation and suggest further research opportunities