Obligatory Passage Point

The concept of Obligatory passage point (OPP) was developed by sociologist Michel Callon in a seminal contribution to actor–network theory: Callon, Michel (1986), "Elements of a sociology of translation: Domestication of the Scallops and the Fishermen of St Brieuc Bay". In John Law (Ed.), Power, Action and Belief: A New Sociology of Knowledge? London, Routledge: 196-233.

Obligatory passage points are a feature of actor-networks, usually associated with the initial (problematization) phase of a translation process. An OPP can be thought of as the narrow end of a funnel, that forces the actors to converge on a certain topic, purpose or question. The OPP thereby becomes a necessary element for the formation of a network and an action program. The OPP thereby mediates all interactions between actors in a network and defines the action program. Obligatory passage points allow for local networks to set up negotiation spaces that allow them a degree of autonomy from the global network of involved actors.

An action program can comprise a number of different OPP's. An OPP can also be redefined as the problematization phase is revisited.

In Callon and Law's '"Engineering and Sociology in a Military Aircraft Project" the project management of a project to design a new strategic jet fighter for the British Military became an obligatory passage point between representatives of government and aerospace engineers.