This volume – like the NATO Advanced Research Workshop on which it is based –  addresses the fundamental science that contributes to our understanding of the potential risks from ecological terrorism,  i.e. dirty bombs, atomic explosions, intentional release of radionuclides into water or air. Both effects on human health (DNA and systemic effects) and on ecosystems are detailed, with particular focus on environmentally relevant low-dose ranges. The state-of-the-art contributions to the book are authored by leading experts; they tackle the relevant questions from the perspectives of radiation genetics, radiobiology, radioecology, radiation epidemiology and risk assessment.