Abstract. A choreography specifies the interactions between the resources of multiple collaborating parties at design time. The runtime management of authorization policies in order to support such a specification is however tedious for administrators to manually handle. By compiling the choreography into enhanced authorization policies, we are able to automatically derive the minimal authorizations required for collaboration, as well as enable and disable the authorizations in a just-in-time manner that matches the control flow described in the choreography. We have evaluated the advantage of this utility in a collaborative engineering scenario.