We describe our motivational analysis of ingroup bias. Central to our approach are two functions of ingroup bias: an identity function (the creation and expression of one's social identity) and an instrumental function (the facilitation of intergroup competition and social change). We present a research programme on the determinants of these two functions in which we have focused on socio-structural factors (group status and status stability), psychological factors (group identification and threat), and strategic considerations concerning the audience to which ingroup bias is communicated. In addition, we relate the different functions of ingroup bias to different forms of ingroup bias (symbolic versus material forms of ingroup bias; ingroup favouritism versus outgroup derogation). Our conclusions centre on the social and diverse nature of motivations underlying ingroup bias, and the integration of identity and instrumental perspectives on this phenomenon.