The Space Agency was a Human organization responsible for the exploration of space after First Contact with the Vulcans.
The Space Agency commissioned the SS Conestoga to colonize Terra Nova in 2069, and also attempted to send a second group of colonists to the planet fourteen years later. (ENT: "Terra Nova")
Given the time frame involved, the Space Agency may have also been responsible for the SS Valiant, which was launched about the same time as the Conestoga.