In 1989 the world witnessed the beginning of a process of fundamental political change in East-West relations including the dismantling of the Berlin Wall, the disappearance of one-party Communist states throughout Central and Eastern Europe, the establishment of free and independent states in the republics of the former Soviet Union, and the end of the division of Europe. The role played by the North Atlantic Alliance, from its establishment in 1949 to the end of the Cold War four decades later, was fundamental in bringing about the conditions which made these developments possible. As the instrument for guaranteeing the security, freedom and independence of its members, maintaining a strategic balance in Europe and promoting democratic values and the emergence of European democratic institutions, the Alliance created the stability which was the precondition for bringing an end to the adversarial relationship between East and West.