The Nigerian Army (NA) is functionally organized into combat arms, which are infantry and armoured; the combat support arms, which are artillery, engineers and signals; the combat support services comprise medical, supply and transport, ordinance and finance. Others include the military police, intelligence, physical training, chaplains, public relations and band.
Training and Doctrine Command (TRADOC) located in Minna is responsible for doctrinal, training and combat development with an R&D outfit. There are 17 Corps Training Schools and an NA College of Logistics (NACOL).
Hierarchically, it is organized into the army headquarters, divisions, brigades, battalions / regiments, companies, platoons and sections. A division is a combined-arms organization with 7,000-22,000 military personnel commanded by a major general. It includes minimum of 2 brigades as maneuver elements, an artillery brigade, a division signals and other supporting elements. A brigade is an organization of units, 3 battalions and other support elements.
A battalion is a reasonably self-sufficient unit. It is the basic unit for combat and support of an army. A platoon consists of 3 sections and commanded by a lieutenant or captain. A section is an organization larger than a squad and smaller than a platoon. The divisions operate combined arms force structures with complements of combat support and combat support services. Each is designed to operate either on its own in special operations or conventionally jointly with the 2 other Services.
The 1990 structure is what existed a decade later. In that exercise, the NA was structured into two Mechanised Divisions, one Armoured Division, a Composite Division, Lagos Garrison Command (LGC) and a Brigade of Guards (for ceremonial duties and Presidential Security). Each Mechanised Division comprised two Mechanised Brigades and an Artillery Brigade complete with the combat support services. By one account the composite division comprised one Amphibious Brigade, one Motorised Brigade, one Paratroop Battalion with their combat support services elements.
Each division and the LGC in addition to having appropriate combat support and services had a Recce Battalion deployed close to Nigeria’s international frontiers within their Areas of Operational Responsibility (AOR) for reconnaissance and early warning. The units and the formations were strategically deployed to enable them provide adequate internal and external security obligations to the country.