For the similarly named animal, please see gorilla.
A guerrilla warfare was a type of warfare that uses non-standard tactics to achieve its goal against an organized military.
During the Galen border conflict of the 2350s, it was a common tactic for the Talarians to abandon their observation craft and rig them to self-destruct, before issuing a general distress call. That guerrilla maneuver alone resulted in 219 fatalities over a three day period. (TNG: "Suddenly Human")
In 2372, faced with the Kazon overrunning USS Voyager, The Doctor briefly considered accessing a tactical database and teaching himself guerrilla warfare, but dismissed the idea, as it would take too long. (VOY: "Basics, Part I")