The Starfleet Wartime Regulations were a set of rules that existed within the Federation Starfleet.
In 2373, during the Virogen Crisis, Captain Jean-Luc Picard envoked Code One under the Wartime Regulations after losing contact with Starfleet Command. After initiating a Code One declaration of war, he took command of a fleet of starships at Vulcan in order to track down the suspected Symmetrist base on the Vulcan homeworld. (TOS novel: Avenger)