This dissertation aims to present a structured overview of the state-of-the-art in cooperative robotics research. As we illustrate in this dissertation, there are several interesting aspects that draws attention to the field, among which 'Life Sciences' and 'Applied AI' are emphasized. We analyse the key concepts and main research issues within the field, and discuss its relations to other disciplines, including cognitive science, biology, artificial life and engineering. In particular it can be noted that the study of collective robot behaviour has drawn much inspiration from studies of animal behaviour. In this dissertation we also analyse one of the most attractive research areas within cooperative robotics today, namely RoboCup. Finally, we present a hierarchy of levels and mechanisms of cooperation in robots and animals, which we illustrate with examples and discussions.