Atopic dermatitis now affects one in five children, and may progress to asthma and hay fever. In the absence of effective treatments that influence disease progression, prevention is a highly desirable goal. The evidence for most existing disease prevention strategies, such as avoidance of allergens and dietary interventions, has been unconvincing and inconsistent. Fresh approaches to prevention include trying to induce tolerance to allergens in early life, and enhancing the defective skin barrier to reduce skin inflammation, sensitisation and subsequent allergic disease. Early and aggressive treatment of atopic dermatitis represents another possible secondary prevention strategy that could interrupt the development of autoimmunity, which may account for atopic dermatitis persistence. Large scale and long term randomized controlled trials are needed to demonstrate that these ideas result in clinical benefit.