The evolution of cooperation to has been a central research focus for decades, and while it is no longer as puzzling, it remains fascinating. Cooperation is a widespread phenomenon in nature, but human cooperation surpasses that of all other species in both scale and complexity. Research on the roles of reputation and punishment on cooperation has provided key insights into the evolutionary stability of the exceptionally high levels of cooperation among humans. However, humans don’t always cooperate—teams that collaborate effectively in one context may fail to do so in another. This talk will explore the evolutionary mechanisms underlying cooperation, using Darwin’s theory of natural selection to explain these patterns. Examples from both human behaviour and the animal kingdom will illustrate these principles.