The Suez Crisis of 1956 is a perfect case for crisis research in the domain of international relations: the events leading to an Israeli attack on Egypt and an Anglo-French military invasion in the Suez Canal area seriously endangered regional and global peace and security. It also had major long-lasting consequences, notably the end of British influence in the Middle East, the expansion of the Cold War into that region, severe damage to the Western alliance, and, related to that, the acceleration of European integration as well as the development of the French nuclear bomb. An analysis of the Suez Crisis allows for a useful comparison of objectivistic and subjectivistic conceptualizations of the notion of crisis. This bears out that different actors attached, and still attach, different meanings to the events of 1956. Consequently, they look back on, and evaluate, the crisis in different terms. Also, Suez invites a confrontation of rationalist and constructivist approaches to the crisis phenomenon in the international relations literature. Furthermore, it invites an assessment of different approaches to foreign policy crisis decision-making, as they are employed in the comparative foreign policy analysis literature. In addition, the crisis serves to dissect important methodological issues regarding crisis research, particularly regarding causality and the issue of the decision unit. Finally, Suez offers insights into the specific legal and normative constraints faced by democracies seeking to go to war.