Sponsored by the Association of Educational Communication and Technology (AECT), the third edition of this groundbreaking Handbook continues the mission of its predecessors: to provide up-to-date summaries and syntheses of recent research pertinent to the educational uses of information and communication technologies. In addition to updating, this new edition has been expanded from forty-one to fifty-six chapters organized into the following six sections: foundations, strategies, technologies, models, design and development, and methodological issues. In response to feedback from users of the second edition, the following changes have been built into this edition. More Comprehensive – topical coverage has been expanded from forty-one to fifty-six chapters and includes many more chapters on technology than in previous editions. Restructured Chapters – this edition features shorter chapters with introductory abstracts, keyword definitions, and extended bibliographies. More International – more than 20% of the contributing authors and one of the volume editors are non-American. Theoretical Focus – Part 1. provides expanded, cross-disciplinary theoretical coverage. Methodological Focus – an extended methodological chapter begins with a comprehensive overview of research methods followed by lengthy, separately authored sections devoted to specific methods. Research and Development Focus – another extended chapter with lengthy, separately authored sections covers educational technology research and development in different areas of investigation, e.g., experimental methods to determine the effectiveness of instructional designs, technology-based instructional interventions in research, research on instructional design models, and design-based research methods. This Handbook is intended for graduate students and their professors, instructional designers and researchers in educational communication and technology plus the libraries that serve them.