Abstract
Most of lifespan research focuses on age-related changes and plasticity as early markers of decline or performance improvements achieved through training interventions. This special issue on functional approaches to lifespan development focuses on age-related stabilization in complex functions such as cognitive and motor performance and well-being on the levels of brain and behavior. One central question focuses on what elements have to change for individually important outcomes to remain stable in old age, putting the many experimental studies on the plasticity of elementary processes in the context of the recognition that aging individuals most often successfully manage their development and maintain high levels of functioning. Aging research will profit from understanding the processes and potentials of lifespan developmental stabilization.