We are interested in the relationships that exist between an individual and his role. We therefore analyze and classify in this paper these relationships and the ways in which an individual’s cognitive framework and behaviour change when playing a role. Our final objective is to integrate these relationships in the field of multi-agent systems, where artificial agents play roles in artificial organizations. However, the analysis presented in this paper is drawn from human societies — the examples used generally involve humans and not artificial agents. We therefore sometimes use the term individual to denote a human or artificial agent playing a role. We will often distinguish between the two cases by using the pronouns it for artificial agents and (s)he for human ones.