This chapter presents varied research reports and methodological approaches to studying teacher pedagogical content knowledge (PCK). The ability of a teacher to fluidly transform this knowledge requires that he or she develops PCK skills, so rich forms of instruction that are pedagogically powerful can be provided. This is the essence of PCK. The author presents a model for the analysis of PCK in engineering and technology education. Additionally, several PCK studies are analyzed to unpack the varied complexities and methodological challenges that researchers have encountered when designing and conducting PCK research. A result of this review of PCK research in engineering and technology education, along with PCK research from associated fields, highlights important questions about the need for a conceptual framework and PCK taxonomy that can help guide and inform future PCK research approaches in engineering and technology.