Teamwork is studied in many disciplines, but there is as yet no comprehensive theory of teams. This collection brings together perspectives on teamwork from evolutionary biology, psychology, economics, robotics, philosophy, management and artificial intelligence. They introduce the reader to state-of-the-art research methods as diverse as laboratory experiments and evolutionary modelling, epistemic logic and the programming of robots. These are directed to answer questions such as: hat is a team? How did teamwork evolve? What factors make for effective teamwork? How do people mediate between conflicting team memberships? How is teamwork learnt?