FN P90

The FN P90 is a personal defense weapon chambered for the 5.7×28mm cartridge, also classified as a submachine gun, designed and manufactured by FN Herstal in Belgium. Created in response to NATO requests for a replacement for 9×19mm Parabellum firearms, the P90 was designed as a compact but powerful firearm for vehicle crews, operators of crew-served weapons, support personnel, special forces, and counter-terrorist groups.

Designed in conjunction with the FN Five-seven pistol and FN 5.7×28mm NATO ammunition, development of the weapon began in 1986, and production commenced in 1990, when it was known as the Project 9.0 (from which the "90" in its name is derived), 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.