This book explores the nature of professional judgement and how it is used in planning, design and management. It is based on two decades of research on the psychology of judgement and its application in professional decision-making. The planning, design and production of engineering are examined in the light of the knowledge of judgement. Conclusions are drawn to improve safety, reliability and the social fit of engineering. Professor Jim Parkin, author of the hugely popular book Management Decisions for Engineers, explores the social forces that are requiring professional engineers to take account of community risks, ecological, sustainability and a growing resistance to technology.