This presentation will help consultants, growers, researchers, and other practitioners to identify production, postharvest handling, and storage factors that influence the physiological age and productivity of seed potatoes. Understanding the physiology of aging and how it affects crop growth and yield will enable the adoption of management practices to control the aging process to optimize tuber set and size distribution for various markets. This presentation will address the effects of seed age on plant growth and development and the utilization of key age-induced growth responses as indicators of the relative physiological age of seed lots. It will also review the sensitivity of cultivars to environmental conditions that accelerate aging. By the end of this presentation, the practitioner should have a solid understanding of the physiological basis of aging of seed potatoes and its consequences for production.