This is a Multi National Company.
- Boeing Commercial Space Company (USA, 40%)
- S.P.Korolev Rocket and Space Corporation Energia (Russia, 25%)
- Kvaerner Maritime a.s. (Norwegian, 20%)
- Production Association Yuzhmashzavod, M.K.Yangel Design Bureau Yuzhnoye, (Ucrania, 15%)

A big ship, the "Sea Launch Commander" carries several rockets inside, with enough space to make the final assembly. And the "Odyssey" platform, a self propeller "ship" designed from oil platforms design.

They ussually navigates to the Ecuator, at the Pacific Ocean. In 2005 there where 5 rockets launched from the Odyssey and in 2006, one.

The Sea Launch Commander was built in Glasgow, Scotland. The part of the ship where the rocket is assemble was made in Saint Petersburg, Russia
The rockets (Zenit-3SL) are russian.
The Odyssey was built in Stavanger, Norwegian

In the pictures above we can see how the Commander "feed" the Odyssey with a Zenith Rocket to be launched.
Once in possition, everybody "runs away" up to 5 km from the Odyssey (just in case something go wrong... ) and they make the final rocket fuel upload and the launch by remote control.



Image Credits: Korolev RSC Energia

Skoogled by me.. I only modeled the Odyssey as the Commander is in the image!