- Crew are required to control ships.
- If you have no crew on a ship then the ship cannot move.
- Crewless ships have a scan range of 0 (Host 213e).
- Crew can participate in ship boarding. Defending crew get a 10x defensive bonus.
- Crew can participate in ground battle.
- Ships starting the turn with 0 Crew cannot Cloak.
 Ship Combat
If a ship has less than 50% crew its weapons will begin to malfunction during combat. The percentage crew that you have is the percentage chance that a weapon system will work.
 Ship Movement
While it is true that a ship without crew can't move, there's an exception. If you transfer crew to the ship before movement, the ship can fully move (both warp and hyp). Transfer can be initiated either by the empty ship or another ship nearby. This even works when the ship in question has life support damage greater than 100. The heroic crew will be killed at end of turn, but until then you have full use of the ship (just beware of combat).
Anyway, nearly all devices of a ship (including laying and sweeping of minefields) can be used without any crew.
 Crew Evolution
- Using Training Centers Colonists can be trained to crew.
- Using Training Centers crew can be trained to Troops.
- The Privateers lack Training Centers but can train Crew on all their ships.
- The Colonies of Man can both build Training Centers and also train Crew on their ships.
- The Aczanny Pyramids can train Crew is a special ground structure called the Air Academy, which doesn't affect growth in the same way that Training Centers do.
- The Cyborg cannot train Crew or Troops. They have special rules where Colonists are converted automatically to Crew or Troops.
- The United Enforcement Authority makes money training Crew (and Troops and High Guard) using their Training Centers.
 Losing Crew
- Crew can be killed during space combat.
- Crew can be killed or captured during ground combat.
- Crew can be killed during Boarding.
- Crew can be taken from a Ground Base using a Crew Abducter. They will become enemy Crew.
- Crew can be taken from a Ship using a Siren HAARP. They will become enemy Crew. Solorians are immune.
 Notes from Tim Help file
Crew Ratings: Ship crews have ratings of happiness, skill and experience. A ships skill level and experience improves over time. The happiness of a crew is improved when a ship wins a battle and when things are going well for their whole race. happiness can be improved by being near a ship with a recreational deck or over a planet with a resort. If the happiness of a crew reaches 0 the crew may mutiny, or maybe even join another race.