The purpose of this study was to describe a process of preparing technology education teachers to teach engineering design concepts in the context of technology education. This process was identified through a study of professional development activities that were organized and conducted by technology teacher education partner universities of the National Center for Engineering and Technology Education (NCETE) to prepare middle school and high school technology teachers to infuse engineering design, problem solving, content, and analytical skills into the K-12 curriculum. A collective multisite case study formed the methodology for this study. Data were collected using individual interview sessions that lasted 30-40 minutes, video materials, observations, and artifacts. A total of 15 interviews were individually analyzed, and then compared through a cross-case analysis. Several sub themes emerged to illuminate the central theme of professional development. These included planning, communities of practice, administration and climate, practitioner needs, activities in the classroom, expertise, meaning making, and assessment. (Contains 4 figures.)