A stated aim in the EU Global Strategy is for the EU to work with partners in addressing crises across the world. This article analyses such potential in the area of crisis response and peacebuilding, with an emphasis on the EU’s interaction with the UN and OSCE. It starts off comparatively by examining where the EU, UN and OSCE add value in crisis response and peacebuilding and reach complementarities. It shows that deployments differ across geographical locations and that the mandates of these organizations vary considerably with the EU focusing on police capacity building, the OSCE on the judiciary and the UN providing monitoring functions. In the second half, the article uses insights from cooperation between these organizations on the ground in Kosovo, Mali and Armenia to determine levels of interaction. Despite relatively few conflicts between these organizations, we find that they continue to work in parallel with each organization focusing on their narrow mandate and competences.