Even though the current situation may give rise to concerns, the European integration process has already experienced severe crises in the past, from the rejection of the European Defence Community in 1954 to the deadlock in the workings of the Community institutions in the early 1980s, in particular during budget negotiations, not forgetting the empty chair crisis between 1965 and 1967, the monetary problems of the 1970s, the thorny question of the UK's accession and financial contribution and the enlargement of the Union towards the south. How were these crises experienced and overcome? Can the historical analysis of these crises, some of which threatened the very existence of the Communities, help us to draw some lessons which can be applied to the present situation? Do these crises differ in nature from the one that we are experiencing today? First-hand witnesses and historians attempt to answer these questions in order to shed some light on the similarities and differences between past and present crises.