The Zenit launch vehicle was first introduced in 1985 but was not announced to the world until 1989.  The Zenit is a highly automated two stage LOX / RP (kerosene) vehicle originally designed to place large (10 metric tonne) spy satellites into LEO polar orbits.  The Zenit's highly automated launch system and large payload capability, as well as its ability to launch in all types of weather, made it the ideal launch vehicle for the Sea Launch International Consortium.  Currently, there are two Zenit configurations, the two stage Zenit 2 and the three stage Zenit 3SL.  The Zenit 3SL uses an NPO Energomash Block DM third stage to transfer satellites into high altitude orbits.  Currently, two and three stage Zenit launches are conducted out of Baikonur.  The Sea Launch Co. operates the Zenit 3SL from a floating platform in the South Pacific to service the GTO market.

Sea Launch Co. was formed in April 1995 to market the Zenit 3SL vehicle internationally to service the lucrative GTO satellite market.  Sea Launch is a joint venture between the Boeing Commercial Space Company of Seattle Washington (40%); RSC Energia of Moscow, Russia (25%); Kvaerner Maritime of Oslo, Norway (20%); and KB Yuzhnoye/PO Yuzhmash of Dnepropetrovsk, Ukraine (15%).  Kvaerner provides the Command Ship, KB Yuzhnoye provides the two stage Zenit launch vehicle, NPO Energia provides the Block DM third stage, and Boeing Commercial Space provides the composite payload fairing and systems integration.  As of May 1999, Sea Launch had a launch backlog of approximately 18 satellites.