WPI has a project-based curriculum that is well suited to the teaching of design. Open-ended design projects are assigned in courses from freshman to senior level, including a year-long senior thesis. A large fraction of these projects are sponsored by industry and thus are real engineering problems. In some cases the students' designs have been prototyped and delivered to the sponsor to be put into use in their laboratories or production facilities. This talk will describe the design education program at WPI and present examples of the types of projects that we assign to students at various levels. It will conclude with some general recommendations for the teaching of mechanical engineering design.