The Ministry of Defence (MoD) is the United Kingdom government department responsible for implementation of government defence policy and is the headquarters of the British Armed Forces.

The MoD states that its principal objective is to defend the United Kingdom and its interests. With the collapse of the Soviet Union and the end of the Cold War the MoD does not foresee any short-term conventional military threat; rather, it has identified weapons of mass destruction, international terrorism, and failed and failing states as the overriding threats to the UK's interests. The MoD also manages day to day running of the armed forces, contingency planning and defence procurement.