The GenoHaradan Bounty Hunters Guild was a secret organization of the most elite bounty hunters in the galaxy. It was formed before the Galactic Republic, and supposed to be disbanded when its founder was killed. The guild, however, simply went underground and stayed behind the scenes in the galactic events to follow.
The guild mainly struck political targets, through which they controlled the Republic.
Only a select few beings in the galaxy knew of the existence of the guild, consisting of a few high-up Senators wanting to control the Senate through the guild, and a select few wise Jedi Masters.
Revan went to Manaan to meet Hulas, a Rodian representative of the guild, where Revan was given his first assassination assignment, which he completed. The next assignment consisted of three much more difficult bounties, each of which were completed by the former Dark Lord. After Revan claimed his bounties, Hulas told him that he had used Revan to usurp the power of the guild by assigning Revan to kill the three other leaders of the guild. Revan was angry at this, and challenged Hulas to a duel.
The duel was organized in the Dune Sea on Tatooine, and Revan was told to come alone. However, Hulas renenged on the agreement and came with six guild members besides himself. Revan defeated them all handily and the guild leaderhsip was shattered. What happened to the guild after that was unknown.