This chapter examines the integration of pedagogical content knowledge in graduate-level biology courses in a secondary teacher preparation program. Given the residency format of the program, expertise from college faculty in biological sciences and education, science educators from a science museum, and educators working with a high school network combined to review, redesign, implement, and assess PCK infused biology courses. Using the lens of action research, we examine the effectiveness of the course modifications, the context of the residents' clinical experience on this process, and the outcomes for the content course and work with high school students. Lessons learned and suggestions for the future are offered. [For the complete volume, "Pedagogical Content Knowledge in STEM: Research to Practice. Advances in STEM Education," see ED613708.]