Account sitting refers to a procedure in which one player allows another user to "look after" their account for reasons such as absence or the inability to access a computer/the internet. For an account sit to be considered "legal", it must satisfy the following conditions:
- A game operator must be consulted.
- The sitter is allowed to use resources on the planet(s) to start construction/research, but s/he may not send out any fleets unless in immediate danger (i.e. fleetsaving, but only when an attack is incoming)
- Each account sit "session" must not exceed 12 continuous hours, but multiple sessions are allowed as long as the account's owner logs in at 12 hour intervals.
The last reason means that Vacation Mode is generally advisable in preference to account sitting if the account owner is going away for an extended period of time (i.e. a holiday).