Over the past two decades, the European Union (EU) has become increasingly involved in preventing conflict and promoting sustainable peace beyond its borders. The EU’s potential to contribute to conflict prevention and peacebuilding is said to be particularly promising given the wide range of instruments and resources that can be mobilised under the EU’s external action. Yet, the EU continues to face key four key challenges in this area: (1) bridging the early warning-response gap; (2) improving cooperation with other international partners in conflict prevention and peacebuilding; (3) enhancing civil–military coordination; and (4) ensuring local ownership. This article introduces these four issues which frame the articles in this Forum. By addressing these four challenges, this Forum sheds light not only on the EU’s role and limitations as a peacebuilding actor, but also on how other international actors might learn from the EU’s engagement in conflict prevention and peacebuilding.