Concessions and leases in international relations

In international relations, a concession is a "synallagmatic act by which a State transfers the exercise of rights or functions proper to itself to a foreign private person which, in turn, participates in the performance of public functions and thus gains a privileged position vis-a-vis other private law subjects within the jurisdiction of the State concerned." International concessions are not defined in international law and do not generally fall under it. Rather, they are governed by the municipal law of the conceding state.

Source: Wikipedia — Concessions and leases in international relations (CC BY-SA 4.0)