The impact of the environment on human health is of growing concern to the public, politicians and public health practitioners. Epidemiology offers a way of investigating and measuring potential hazards, from local sources of pollution to global climate changes. It allows real effects to be distinguished from chance associations. This book describes the methods available for public health practitioners to enable investigations to be carried out and how findings should be interpreted to ensure that the most appropriate policies are adopted. The book examines: air pollution; clusters of cases of ill-health; radiation and hazardous waste; water and health; and, climate change. Contributors include: Mike Ahern, Ben Armstrong, Araceli Busby, Pat Doyle, Shakoor Hajat, Sari Kovats and Paul Wilkinson.