Attention and Effort is Daniel Kahneman's groundbreaking study of how the human mind allocates its limited mental resources. Drawing on experimental psychology, physiology, and cognitive theory, Kahneman explores what it really means to concentrate, why mental effort feels costly, and how attention is shaped by motivation, fatigue, and competing demands. Long before the language of 'cognitive load' and 'limited bandwidth' became commonplace, Kahneman was pioneering these ideas, showing that attention is an active, effortful process - one that governs perception, performance and decision-making. His account of mental effort laid the foundations for later work on judgment and ultimately for the field of behavioural economics. Rigorous and intellectually ambitious, Attention and Effort remains essential reading for psychologists, neuroscientists, economists, and anyone interested in how the mind works under pressure. This new edition features a new introduction from neuroscientist and author of The Organised Mind, Daniel Levitin, who was also a collaborator of Kahneman's. Attention and Effort allows readers to rediscover the early thinking of a scholar whose ideas would go on to change how we understand rationality itself.