Book excerpt: The 2nd edition of the Handbook of Technological Pedagogical Content Knowledge (TPACK) for Educators addresses the concept and implementation of technological pedagogical content knowledge—the knowledge and skills that teachers need in order to integrate technology meaningfully into instruction in specific content areas. Driven by the growing influence of TPACK on research and practice in both K-12 and higher education, the 2nd edition updates current thinking about theory, research, and practice. Offering a series of chapters by scholars in different content areas who apply the technological pedagogical content knowledge framework to their individual content areas, the volume is structured around three themes: Current thoughts on TPACK Theory Research on Technological Pedagogical Content Knowledge in Specific Subject Areas Integrating Technological Pedagogical Content Knowledge into Teacher Education and Professional Development The Handbook of Technological Pedagogical Content Knowledge (TPACK) for Educators is simultaneously a mandate and a manifesto on the engagement of technology in classrooms.