Assassin bureau
There is an Assassin's Bureau in all three cities, it's basically a safe house for the Guild. The assassin's bureau's leader provides you with useful tips on where to get your information. As soon as you acquire enough information the leader will provide you with what appears to be one of the primary flight feathers of a white eagle, which is yet another nod towards the resemblance that Altair shares with the birds. Once you have collected all the information on an assassination target and it is possible to do so before entering the Bureau, the leader of the bureau within that city provides you with that same which is used to claim an assassination by running the feather through the blood of the mark. As proof of the assassination, Altair must return to the Bureau and present it as proof of his deed. The assassin's bureau will be closed when your current social status is revealed, to prevent guards from discovering the bureau and also to not have you violate the creed (never bring attention onto the brotherhood). The Assassin Bureau is a place where they also make swords, blades and other uselfull equipment.
Altair Was a bureau leader in Damascus Malik is the bureau leader in Jerusalem.