This book describes mechanisms of skin damage generation and examines the potential impact of free radicals, reactive oxygen species (ROS) and oxidative damage on the skin ageing process. It also evaluates methods to decrease skin oxidative stress, oxidative damage, and skin ageing. The identification of free radical reactions as promoters of the skin ageing process implies that interventions aimed at limiting or inhibiting free radical reactions should be able to reduce the rate of formation of ageing-related changes with a consequent reduction of the ageing rate. This book highlights how ageing of the skin happens, as well as what are the causes and the best ways to prevent and treat it.