This paper presents a formalisation of obligations, social commitments and roles for BDI agents. We present a formal analysis of general obligations and relativised-to-one obligations from a bearer to a single counterparty and we examine obligations and relativised-toone obligations in the context of strong realism for BDI agents. We also discuss how relativised-to-one obligations arise as a result of social commitments and the adoption of roles. In our framework, if an agent adopts a role, then this role is associated with one or more social commitments. Social commitments give rise to relativised obligations and consequently, roles, social commitments and relativised obligations are interwoven.