This Note uses de-escalation dynamics to examine some military aspects of the broader subject of crisis management as it might be practiced by NATO, and then explores the future role of NATO in European security. Europe is undergoing what may be an extended period in relaxation of tensions between the two major power blocs. The past implausibility of rapid reduction of tensions should make us wary of forecasts that the current process is irreversible. The author draws an analogy between the lack of Alliance preparation for the pace of relaxation of tensions currently in progress in Europe and a similar lack of planning and exercising for de-escalation in a future crisis. The Note presents an argument for NATO addressing its need for crisis-management capabilities, and more specifically, for the ability to manage de-escalation and force disengagement in crisis. The author posits four types of scenarios — a major Soviet reentry in Eastern Europe, civil conflict in Eastern Europe, a local cross-border war in Europe, and an out-of-area conflict with NATO implications — which suggest three areas that need improvement — planning, forces and hardware, and political frameworks.