The RSD-10 Pioneer ( tr.: Raketa Sredney Dalnosti (RSD) "Pioneer"; ) was an intermediate-range ballistic missile with a nuclear warhead deployed by the Soviet Union from 1976 to 1988. It carried GRAU designation 15Zh45. Its NATO reporting name was SS-20 Saber. Its deployment was a major cause of the NATO's 'Double-Track Decision', which led to the deployment of more medium-range nuclear weapons in Western Europe. The RSD-10 was withdrawn from service under the 1987 Intermediate-Range Nuclear Forces Treaty.