Cold War Berlin Contingency Planning was an important series of developments which heralded the establishment of NATO's Flexible Response strategy, a significant benchmark in the history of Western strategic thought and the place of nuclear weapons in it. Highly secret at the time, examining the BERCONs reveals the fears and aspirations of NATO policy-makers, particularly in the Kennedy administration which presided over the two most visible and dangerous Cold War confrontations: Berlin and Cuba. The BERCON process also demonstrates that the United States could be influenced by its allies, particularly Canada, in the development of NATO strategy.