JOINT is a project aimed at assessing challenges to a more joined-up foreign and security policy of the EU. These challenges – multipolar competition, regional fragmentation and internal contestation – have been mounting in recent years. Systemic shifts such as the dwindling global engagement of the United States and the growing assertiveness of Russia and China hamper the ability of the EU and its member states to shape multilateral rules and compel them to rethink their role along new patterns of multipolar interactions. Additionally, the collapse or severe weakening of state authority and governance in the EU’s neighbourhood (and beyond) create interconnected challenges extending into policy areas outside the traditional remit of foreign and security policy, thus augmenting the need for an integrated response. Lastly, the emergence of nationalist forces within the EU, which often espouse Eurosceptic views, complicates efforts to reach intra-EU consensus on international security matters. These challenges affect the capacity of the EU and its member states to reconcile security priorities, allocate the resources to pursue these, and engage with external actors accordingly. The interplay between these factors is most evident in the EU’s difficulty in addressing crises and conflicts, especially in its surrounding regions. JOINT, an interdisciplinary project involving 14 partners from 12 countries, investigates how to make EU foreign and security policy governance structures more joined-up and sustainable in a rapidly changing and contested international environment.