This introduction sets forth the thinking that guided the journal’s special issue on youth health and well-being. Three main points provide the foundation: (a) that youth development is predicated on a strengths-based approach, (b) that an ecological approach to youth health is essential for real and lasting change, and (c) that the larger intent of youth development is encompassed in increasing youth well-being, of which youth health is a key component. The guest editors provide an overview of the articles included in the special issue. The articles highlight different settings, describe the processes involved in developing programs, and address organizations’ efforts to enhance youth health and well-being. The reader will also find resources and models that are suitable for use across youth development settings.