Melting glaciers, denuded slopes, expanding deserts these images of environmental change have long captured public attention. With the threat of global climate change, the environment has moved from casual concern to the forefront of the international agenda. The scale of change is so great that society must now address the challenges of adapting to an altered environment while at the same time strengthening efforts to prevent further damage. Scientists and decision makers have only recently recognized the need for policy to tackle the complexity of this interaction. Growing interest in adaptation to climate change is evidence of this realization. The scientific community now stresses that both the underlying causes of human vulnerability to hazards, and the role of environmental conditions in exacerbating those hazards should be taken into account. This discussion paper aims to address the complexity of risk in this 'two-way system' between environment and human societies.