The introductory paper to this Special Issue discusses the idea of crisis in relation to European integration from a historical perspective in order to contextualize four different current events in the European Union (EU) in turn – euro area crisis, migration crisis, Brexit, and the rise of populist responses to EU governance. We turn to the wider scholarly concept of ‘crisis’ and apply it to large-scale events affecting the EU, in order to relate events to broader theoretical discussions about the progression of the EU. Existing literature on the topic highlights different varieties of crisis scenarios: those that undermine the basic integrity of the undertaking; those that threaten certain domains or the activities of certain groups; and those that reflect short-term, but acute dangers that may be overcome without structural damage. This introductory contribution situates each of the four above-mentioned ‘crises’ in the context of these varieties and offers suggestions for how each crisis might influence the future direction of European integration by using illustrations from each of the articles in this special issue.