The Handbook on Implementation Science provides an overview of the field's multidisciplinary history, theoretical approaches, key concepts, perspectives, and methods. By drawing on knowledge concerning learning, habits, organizational theory, improvement science and policy research, the Handbook offers novel perspectives from a broad group of international experts in the field representing diverse disciplines. The editors and authors seek to advance implementation science through careful consideration of current thinking and recommendations for future directions. Featured key concepts include strategies, context, outcomes, fidelity, adaptation and sustainability. Chapters introduce topics, define them, and explain their application in implementation science with examples that resonate with a diverse readership including implementation researchers, instructors, students and practitioners with experience in the field ranging from novices to experienced scholars. Contributors include: G. Aarons, B. Andersson-Gare, M. Bender, S. Bernhardsson, S. Birken, K.A. Blase, A. Bunger, P. Cairney, C. Carroll, D. Cragun, G. Curran, D. D'Lima, L. Damschroder, K.S. Dickson, J. Edwards Becan, A.C. Eldh, P.-E. Ellstroem, T. Finch, D.L. Fixsen, B. Gardner, T. Greenhalgh, E. Haines, G. Harvey, H. Hasson, M. Hatch, S. Hwang, A. Kirk, A. Kitson, J. Leeman, L. Lennox, F. Lorecatto, J.C. Lowery, C. May, N. McCleary, S. Michie, J.C. Moullin, M. Neher, P. Nilsen, R.Y. Nooraie, J. Phillips, S. Potthoff, J. Presseau, E. Proctor, T. Rapley, C.M. Reardon, J. Rycroft-Malone, K. Seers, N. Sevdalis, F.F. Sniehotta, N.A. Stadnick, J. Thor, T. Waltz, J. Wassar-Kirk, B. Weiner, T. Wiley