AbstractThe goal of this article is to explore the utility of integrating two lines of research on questions of modifiability or plasticity of human development. The first line, dealing with the notion of resilience, originated within the field of clinical developmental research. The second line, concerned with developmental reserve capacity, evolved primarily within the field of life-span developmental psychology. Resilience addresses questions of maintenance and recovery of adaptation in the face of stress. In addition, ideas about levels of reserve capacity, rooted in life-span developmental psychology, emphasize the potential for growth. A review of research in the areas of cognitive and self-related functioning provides evidence for resilience as well as developmental reserve capacity in adulthood and old age. It is argued that across the life span reserve capacity is increasingly allocated to resilience-related processes (maintenance of functioning and recovery from dysfunction) rather than growth. A model of successful aging is discussed which suggests that, by means of selective optimization with compensation, old age nevertheless continues to hold the potential for selective growth.