A fireteam is a small military sub-subunit of infantry designed to optimize "bounding overwatch" and "fire and movement tactical doctrine" within a hostile urban environment. Depending on mission requirements, a typical fireteam consists of 4 or fewer members; a grenadier, an automatic rifleman, a rifleman, and a designated team leader; the role of each fireteam leader is to ensure the fireteam operates as a cohesive unit. Two or three fireteams are organized into a squad or section in coordinated operations, which is led by a squad leader.