From the introduction:
Guilds and Orders is a simple resource guide for use at almost any table and any roleplaying game. It lists several possible guilds or orders that you can port into your game and use to augment an adventure through role playing. It's a book that adds depth to a region by giving its people that much more flavor. Below you'll find outlined several guilds and orders, that serve as ready to play creations or as examples of what they should look like. There are entries from the commonly known thieves' guild to the less remembered trade guilds. Whatever the listing, there is more than enough fodder for everyone.
This book is wholly system neutral. The material is good for any role playing game. For that reason, nothing is stated out, guild leaders are not listed, nor any stats given for the rank and file. The few exceptions limit information to hit dice and level. This allows anyone to use it in any game. Where listed, the information is self-explanatory.