Guilds are groups of individuals that band together for common cause. A development of Terrestrial unions they started as a means to help each other and resist the predations of company managements but, over time, developed a support for wider purposes. Guilds tend to be secretive and, although people are technically allowed to be members of more than one guild, the practice is discouraged since it results in loyalty conflicts. Movement between guilds is accepted but viewed with suspicion particularly if an individual is moving from one guild to another similar one with no easily apparent benefit. The most notorious example of a secretive group is The Assassins Guild, an organisation of trained killers that live by one simple rule, "Assassins kill, get killed but don't talk." Membership of The Assassins Guild protects assassins on legitimate missions are protected from prosecution for all actions as long as no significant collateral damage results. In legal terms, this means the commissioning party will be held responsible for all "legitimate" actions taken by the assassin, something that is aided by the guild's ability to withhold information, and the covert manner such commissions are agreed. Other examples of guilds are:
- The Medical Guild: A group dedicated to defending the rights of medical and hospital staff.
- Discovery Guild: A group that protects the interests of science researchers and inventors.
- The Spacer's Guild: Almost all non-military spacer's are members of this group.
- The Merchant's Guild: A group that protects trade rights and mediates on trading disputes.
- The Transport Guild: A group protecting the rights of people involved in the transportation of goods and people.
- The Seaman's Guild: Similar to The Transport Guild but for seafaring workers only.
- The Masters Guild: More of an advisory body that only operates openly in nations that tacitly condone human trafficking.
- The Midnight Guild: Similar to the Masters Guild but protecting thieves and more wide-ranging.
- The Mercy Guild: A guild dedicated to providing aid to planets/states in catastrophe.
- The Free AI Guild: A new guild started by a retired military AI and a human scientist. Their general philosophy is that AIs should have equal rights to humans.