Inside the clan are subsections called guilds. Guilds are used to seperate members into different categories depending on what profession they think can contribute best to the clan. The guild you are in usually depends on your level in a certain skill, although all members are welcome to improve their skills in a guild.
Each guild is given the freedom to basically govern itself with little interference from the rest of the clan. While still maintaining unity and working together, the guild operates its own economy within the clan. The guild leader and officers under the leader enforce and regulate the rules- to a limit. If that power is abused, retribution will be swift and harsh.