A fire team is the smallest recognized military unit. As an army unit it consists of four to five (4-5) soldiers under a non-commissioned fire team leader. Often the fire team is responsible for operating one heavy weapon such as a heavy machine gun or a piece of artillery. Two fire teams form a squad.

The United States Army particularly emphasizes the fire team concept, as do most Special Operations units. Many other armed forces see the squad as the smallest military unit; some countries' armies have a "pair" consisting of two soldiers as the smallest military unit.

The British Army also uses the fire team. An infantry section of eight men usually contains two fire teams (charlie and delta), each comprising an NCO (corporal or lance corporal) and three privates, one of whom carries an LSW.

In the Canadian Army "fire team" refers to two soldiers, with two fire teams forming a group and two groups forming a section of 8 soldiers.

A US Ranger fire team consists of 4 soldiers equipped with a personal weapon and special equipment based on position.

• Team leader,
• Grenadier, grenade launcher
• Automatic Rifleman, machine gun
• Rifleman, Communications equipment

Fire teams have their origins in the early 20th century. From the Napoleonic War until World War I, military tactics involved central control of large numbers of soldiers in mass formation where small units were given little initiative. This resulted in a trench warfare stalemate on the Western Front. In order to combat this stalemate, the Germans developed a doctrinal innovation known as infiltration tactics, in which small, autonomous teams would covertly penetrate Allied lines.

The creation of effective fire teams is seen as essential for creating an effective military as they serve as a primary group. Psychological studies by the United States Army have indicated that the willingness to fight is more heavily influenced by the desire to defend and avoid a loss of face among other members of the fire team and the squad than by abstract concepts.

See also military science.