This book aims to inform health professions educators, including clinical teachers, educational leaders, policy makers, and faculty developers, about the scope and practice of faculty development. It is also designed to review the relevant literature in the field, describe current best practices, and outline future directions. This introductory chapter will address what is meant by ‘faculty development,’ the context in which faculty development occurs, core concepts that underlie the design and implementation of diverse faculty development initiatives, including adaptive expertise, and theoretical frameworks that can guide both research and practice in this increasingly important area of professional development.