The seven major Western suppliers of missile technology (United States, Japan, United Kingdom, West Germany, Italy, France and Canada) established the Missile Technology Control Regime (MTCR) in 1987.
Since that time membership has increased to 34 participants. The MTCR aims to limit nuclear weapons proliferation by controlling the transfer of missile equipment, complete rocket systems, unmanned air vehicles, and related technology for those systems capable of carrying a 500 kilogram payload at least 300 kilometres, as well as systems intended for the delivery of weapons of mass destruction (WMD).
In 1992 the MTCR was extended to cover missile or related systems capable of carrying smaller chemical and biological payloads. MTCR controls are not intended to hinder cooperation in civil space projects.