The breakup of the Soviet Union left a cold war nuclear legacy consisting of tens of thousands of nuclear weapons and a sprawling infrastructure for their production and maintenance. This book examines the fate of this vast nuclear weapon complex and the unprecedented non-proliferation challenges associated with the breakup of a nuclear weapon state. It describes the high-level diplomatic bargaining efforts to consolidate in Russia the nuclear weapons based in newly independent Belarus, Kazakhstan and Ukraine and to strengthen central control over these weapons. It surveys the problems associated with dismantling nuclear weapons and the difficulties involved in safely storing and disposing of large stockpiles of fissile material. It reviews the key provisions of the principal nuclear arms control measures and initiatives, including the START I and START II treaties. Finally, the book assesses the contribution of international assistance programmes to the denuclearization process under way in the former Soviet Union.