The Summer School is organised in the context of the EUDIPLO project. The programme focuses on the role of the EU as a diplomatic actor in the world. The European External Action Service (EEAS) celebrated its tenth anniversary in 2020. The Union’s delegations (more than 140) in recent times have assumed ‘state-like’ functions on the basis of the adoption of diplomatic rules that were originally created for states only. The summer school explores both the internal and external constraints that the EU diplomacy may face in performing its activities. In particular, the speakers will address three issues: the ways in which the EU interacts with Member States’ embassies in third countries; the EU’s relations with selected third States such as the United States, Canada and Russia; Turkey and China’s increasing engagement in Africa and in other contexts. At the same time, the Summer School will present opportunities for the EU to enhance its influence: the speakers will discuss the EU’s role in the Western Balkans, vaccine diplomacy and the EU’s engagement in shaping ambitious rules in multilateral agreements with regards to climate change. The speakers in the programme will also shed light on the way the EU interacts with the United Nations and regional international organizations (such as the African Union or the ASEAN).