The study of health behaviors and fostering health-behavior change is an important endeavor even in old age. The aim of this viewpoint article is threefold. First, we use a broad perspective for the definition of health behaviors to capture all relevant aspects of health-behavior change in older adults. Particularly, we suggest a distinction between proximal (e.g., physical activity) and distal health behaviors (e.g., social participation). Second, we recommend a stronger orientation towards processes in order to study health behaviors and the design of health-behavior change interventions. Third, we review the advantages of a developmental perspective in health psychology. Future directions in the study of health behavior among older adults are discussed.