Although different disease trajectories, care contexts, and policy issues influence feasible intervention delivery in every country, common behavioural and emotional circumstances frequently arise during palliative and end-of-life care. In our second book, Perspectives on Palliative and End-of-Life Care: Disease, Social and Cultural Context, many of these contextual issues are considered. In this book, we focus on behavioural interventions and issues of diversity and intersectionality that must be considered in such interventions. This introductory chapter will define what is meant by a “behavioural” intervention and provide justification for the importance of behavioural and psychosocial interventions in palliative and end-of-life care using an international lens. An overall framework for this volume is described, including: 1) the history of the hospice and palliative care movement, 2) a review of relevant theoretical underpinnings, including the biopsychosocial model as well as lifespan and stress and coping theories, 3) diversity and intersectionality among individuals and families across the course of end-of-life planning and care, 4) the complexities of conducting intervention research with individuals and families near the end of life and across disease and environmental contexts, and 5) a broad overview of chapter content. The overarching goal of these texts is to offer accessible resources for scientists, practitioners, and trainees with relevant information on behavioural mental health and wellness interventions in palliative and end-of-life care across a variety of contexts.