We present an organisation infrastructure for open MultiAgent Systems built upon a role-based access control model (RBAC), which provides agents with means to enable and control actions toward the other entities in the MAS (agents and resources). In particular, an Agent Coordination Context (ACC) is created and assigned to an agent as it enters the MAS, which acts as a sort of private interface for the agent towards the environment: any agent action is thereafter enabled and controlled by that ACC, which prevents those behaviours that are incorrect with respect to the role(s) played by the agent. To this end, each role is assigned a policy that flexibly specifies possible/allowed actions and perceptions over time. Categories and Subject Descriptors D.2.10 [Software Engineering]: Design; I.2.11 [Distributed Artificial Intelligence]: Multi-agent Systems General Terms Languages, Design Keywords Agent Coordination, Agent Infrastructures, Role-Based Access Control