FN P90

The FN P90 is a selective fire personal defense weapon (PDW) designed and manufactured by FN Herstal in Belgium. The P90's name is taken from 1990, the year it was introduced. The P90 was created in response to NATO requests for a replacement for 9×19mm Parabellum firearms; it was designed as a compact but powerful firearm for vehicle crews, operators of crew-served weapons, support personnel, special forces and counter-terrorist groups.

The P90 was designed by FN in conjunction with the FN Five-seven pistol and FN 5.7×28mm ammunition. Development of the P90 began in 1986, and production commenced in 1990, whereupon the 5.7×28mm ammunition was redesigned and shortened. A modified version of the P90 with a magazine adapted to use the new ammunition was introduced in 1993, and the Five-seven pistol was subsequently introduced as a companion weapon using the same 5.7×28mm ammunition.

The P90 was developed and initially marketed as a personal defense weapon, but it could also be considered a submachine gun or compact assault rifle. Featuring a compact bullpup design with an integrated reflex sight and fully ambidextrous controls, the P90 is an unconventional weapon with a futuristic appearance. Its design incorporates several innovations such as a unique top-mounted magazine and FN's small-caliber, high-velocity 5.7×28mm ammunition.

The P90 is currently in service with military and police forces in over 40 nations, such as Austria, Brazil, Canada, France, Malaysia, Poland, and the United States. In the United States, the P90 is in use with over 200 law enforcement agencies, including the U.S. Secret Service. The standard selective fire P90 is restricted to military and law enforcement customers, but since 2005, a semi-automatic carbine version has been offered to civilian shooters as the PS90.