Our skin changes as we age. It becomes thinner and loses fat, making it less plump and smooth. Clinically, aged skin is characterized by wrinkles, sagging, age spots and dryness. Emphasizing laboratory and clinical research, this book comprehensively describes the molecular mechanisms of human skin-aging and age-related skin diseases. This includes molecular understanding of the development of aging skin and its prevention as well as mechanisms-based clinical rejuvenation. The book also focuses on research to develop mechanisms-based anti-skin-aging products.