Engineering design is a critical skill for integrating and applying engineering knowledge. A, validated method to assess engineering design knowledge, however, does not exist. Such a method would allow educators to systematically determine the most effective approaches for helping students learn about engineering design. We are developing such an assessment tool and seek to further evaluate its validity. In this work-in-progress, practicing engineers have completed a design process knowledge assessment tool and their responses will be compared to those of undergraduate engineering students. The current status of the project is that we have gathered responses from twenty-six practicing engineers. These results should be analyzed prior to the conference.