This Handbook 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. Recognizing, for example, that effective uses of technology in mathematics are quite different from effective uses of technology in social studies, teachers need specific preparation in using technology in each content area they will be teaching. The Handbook of Technological Pedagogical Content Knowledge for Educators is simultaneously a mandate and a manifesto on the engagement of technology in classrooms based on consensus standards and rubrics for effectiveness. As the title of the concluding chapter declares, "It’s about time!"