A Guide to Thieves' Guilds

Written for Old School Essentials but usable with any old-school style rpg, or even more modern versions, A Guide to Thieves' Guilds provides rules for players to establish, run, and build a thieves' guild as part of domain-level play and for Referees to create and populate cities with guilds for the players to interact with.
 
This is a 42 page pdf.