Blakemore and Mills (2014) present the hypothesis that adolescence is a ‘sensitive period’ for social cognitive processes. These support the navigation of complex and intimate relationships that continue to develop throughout adolescence. The paper describes the functional and structural changes occurring in areas of the ‘social brain’ during this period and discuss how they relate to navigating the social environment. Also included is a discussion of the importance of considering the social environment and social rewards in research on adolescent cognition and behaviour and suggestions about the potential implications of this research for society.