The hidden curriculum (HC) in health professional education comprises the organizational and institutional contexts and cultural subtexts that shape how and what students learn outside the formal and intended curriculum. HC includes informal social processes such as role modeling, informal conversations and interactions among faculty and students, and more subterranean forces of organizational life such as the structure of power and privilege and the architectural layout of work environments. For better and sometimes for worse, HC functions as a powerful vehicle for learning and requires serious attention from health professions educators. This volume, of interest to medical and health professionals, educators, and students, brings together twenty-two new essays by experts in various aspects of HC. An introduction and conclusion by the editors contextualizes the essays in the broader history and literature of the field.