David B. Rosengren, PhD, is President and CEO of the Prevention Research Institute, a private nonprofit organization in Lexington, Kentucky. He is a clinical psychologist with a broad background in treatment, research, training, and administration. Previously, he was a research scientist and consultant at the University of Washington's Alcohol and Drug Abuse Institute, and worked as a motivational interviewing (MI) consultant and trainer. Dr. Rosengren helped to establish the Motivational Interviewing Network of Trainers, an international association representing more than 1,500 MI trainers spread across more than 40 countries and six continents. His research interests include mechanisms of change for clients and practitioners, training methods, and implementation and dissemination science. He has written journal articles and book chapters on addictions, MI, training, and the change process.

Lynne H. Johnston, PhD, DClinPsych, is a consultant clinical psychologist in the National Health Service and in private practice in the United Kingdom. Dr Johnston has significant clinical, research, training, and consultancy experience. She is member of the Motivational Interviewing Network of Trainers (MINT) and a founding member of MINT UK and Ireland. She has worked as a MI consultant, trainer, and supervisor since 2001 and delivers training to professional groups across the United Kingdom and internationally. Dr. Johnston is Honorary Associate Professor at the University of Glasgow and Visiting Professor at the University of Sunderland, United Kingdom. She is currently supervising doctoral research in training, supervision, and practitioner skill development. She has authored journal articles and book chapters on clinical formulation, MI, training, supervision, and program evaluation.

Charlotte E. Hilton, PhD, is a Chartered Psychologist in the United Kingdom with expertise across health, social care, and high-performance sport settings. She is an active member of the Motivational Interviewing Network of Trainers (MINT) and MINT UK and Ireland, and is passionate about supporting people through change and growth. Dr. Hilton regularly delivers MI training to people who work in a diverse range of professions, and has a history of working within mental and public health settings and primary care. She practices and writes from an evidence-driven perspective, with the intention of having practical utility and an applied focus. Dr. Hilton is a Visiting Fellow at the University of Derby, United Kingdom, and Associate Professor at the University of Florida.