Section 31 is the closest approximation the Federation has to a secret service, a branch of Starfleet whose stated mission is to ensure the continued existence of the Federation for all time, at all costs. Its name derives from the fact that it was created as a secret service through a loophole in section 31 of the original Federation charter.

In practice it tends to represent the more conservative elements of the Federation, and is generally opposed to any large-scale political machinations which it perceives as running counter to its best interests.

It was the founding interest for Temporal Investigations, with the intent of ensuring Starfleet's continued existence against potential invasions by unfriendly or hostile time-travellers; however, Temporal Investigations rejected the somewhat hardline attitude of its superiors and was promoted to a primary divisional role in the Federation hierarchy.