TPACK (technological pedagogical content knowledge) has emerged as a clear and useful construct for researchers working to understand technology integration in learning and teaching. Whereas first generation TPACK work focused upon explaining and interpreting the construct, TPACK has now entered a second generation where the focus is upon using the construct in both research and development projects. In this paper, the TPACK construct is defined and several current research and development projects that use the TPACK framework are described. The strength of the TPACK framework in research and evaluation work in technology integration is discussed, along with future directions for this work. (Contains 1 figure and 2 tables.)