Counter-Terrorists are characters specially trained and/or devoted to preventing terrorist activities and hunting down known terrorists either to capture in order to bring to justice or eliminating with lethal force if they are deemed too dangerous to be kept alive - most are highly skilled law enforcement, military or similar but others have origins as freedom-fighters or similar and are forced into the role either via personal tragedy or a desire to rid the world of dangerous criminals.

Due to its very nature counter-terrorism overlaps heavily with law-enforcement and peacekeeping, if a counter-terrorist is not authorized they are, obviously, also a type of vigilante - also most superheroes will also be a form of counter-terrorist due to the extreme conditions they fight in and the often extremely destructive opponents they face on a regular basis.