Book excerpt: Agency has two meanings in psychology and neuroscience. It can refer to one's capacity to affect the world and act in line with one's goals and desires--this is the objective aspect of agency. But agency can also refer to the subjective experience of controlling one's actions, or how it feels to achieve one's goals or affect the world. This subjective aspect is known as the sense of agency, and it is an important part of what makes us human. Interest in the sense of agency has exploded since the early 2000s, largely because scientists have learned that it can be studied objectively through analyses of human judgment, behavior, and the brain. This book brings together some of the world's leading researchers to give structure to this nascent but rapidly growing field. The contributors address questions such as: What role does agency play in the sense of self? Is agency based on predicting outcomes of actions? And what are the links between agency and motivation? Recent work on the sense of agency has been markedly interdisciplinary. The chapters collected here combine ideas and methods from fields as diverse as engineering, psychology, neurology, neuroscience, and philosophy of mind, making the book a valuable resource for any student or researcher interested in action, volition, and exploring how mind and brain are organized.