Fictional organization from the 80's Star Frontiers science fiction RPG by TSR. The name is a shameless ripoff of Star Trek's United Federation of Planets.
The UPF is the interstellar governing body that protects Frontier space from outside aggression, and functions, much like the UN, as a forum for resolving altercations between its member planets.
It is governed by the Council of Worlds, composed of delegates from each member planet, as well as observers from the most powerful megacorporations. It funds and controls Star Law, which fights crime outside the jurisdiction of its member planets, and Spacefleet, the most heavily armed force in Frontier space, to defend both against Sathar incursion and pirate attacks.
The UPF's jurisdiction does not extend to the surface of its member planets, only to orbit. It is also not allowed to influence or manipulate a member government, thus its members range from utopian democracies, to corporate worlds, all the way to totalitarian dictatorships and criminal-ruled near-anarchies. It does not apply to non-member planets, however - unlike Star Trek's "Prime Directive", the UPF and its agents are free to make contact, trade, and help primitive civilizations, usually to protect them against the Sathar.