From the Publishers website:
Now, Sanctuary is yours to explore with the Thieves' World Player's Manual, the definitive d20 System guide for creating characters and playing in this classic and vibrant fantasy setting.
Explore the Maze, enjoy the delights of the Street of Red Lanterns, or take part in the fight against Dyareela's cultists. The dark and dangerous streets of Sanctuary hold both great reward and dangers beyond imagination. The Thieves' World Player's Manual is your gateway to adventure!