The necessity of balancing risks and benefits impinges on most people's lives, and a broad audience will find this book thought-provoking and useful. They include all those concerned with the management of technology--scientists, engineers, policy-makers and regulators, as well as a growing number of concerned citizens--and all those interested in the nature of decision processes, including psychologists, management and political scientists, and their students. The book presupposes no mathematical or technical background on the part of readers.