The T-72 is a family of Soviet/Russian main battle tanks that entered production in 1969.^[​10] The T-72 was a development of the T-64, which was troubled by high costs and its reliance on immature developmental technology. About 25,000 T-72 tanks have been built, and refurbishment has enabled many to remain in service for decades.^{[​11][​12]} It has been widely exported and has seen service in 40 countries and in numerous conflicts. The T-90 introduced in 1992 is a development of the T-72B;^[​13] production and development of various modernized T-72 models continues today

Development from the T-64

The T-72 was a product of a rivalry between design teams. Morozov KB was led by Alexander Morozov in Kharkiv. Uralvagon KB was led by Leonid Kartsev in Nizhny Tagil.^[​14]

To improve on the T-62, two designs based on the tank were tested in 1964: Nizhny Tagil's Object 167 (T-62B) and Kharkiv's Object 434.^[​14]

Ob. 434 was a technically ambitious prototype. Under the direction of Morozov in Kharkiv, a new design emerged with the hull reduced to the minimum size possible. To do this, the crew was reduced to three soldiers, removing the loader by introducing an automated loading system.^[​15]

Ob. 167 was designed based on an Object 140 rebuilt by Kartsev and Valeri Venediktov. Ob. 167 was more advanced than Kartsev's Ob. 165 and Ob. 166, and was also Kartsev's favored model. In October 1961, when asked to ready Ob. 166 for production, Kartsev disagreed and instead offered to prepare the Ob. 167. This suggestion was rejected, and the Ob. 166 and Ob. 165 were readied as the T-62 and T-62A respectively. Unlike the Kharkiv tank, it eschewed the state-of-the-art. Prototypes used the turret from the T-62, and a manual loader. In 1964, the tank underwent comparative testing with the Ob. 434, in which the former proved its superiority to both the T-62 and T-55. Ob. 167 was favored by Uralvagonzavod director I.V. Okunev and Soviet Premier Nikita Khrushchev, who believed the tank was more affordable. Deputy Chairman of the Council of Ministers of the Soviet Union Dmitry Ustinov, believed the parallel development of Ob. 167 jeopardized the future of the Kharkiv tank. In December 1962, the Council of Ministers of the Soviet Union ordered Ob. 432 (later serialized as the T-64) into production, dooming Kartsev's tank.^[​16]

Kartsev continued to work on the Ob. 167. Ob. 167M incorporated an autoloader. This model too was rejected in May 1964.^[​16]

Problems with the early production run were evident from the start, but a strong lobby formed around Morozov who advocated for Ob. 434 in Moscow, preventing rival developments and ideas from being discussed.^[​17] Ob. 434 was accepted into Soviet Army service in May 1968 as the T-64A.^[​18]

The T-64's smaller design presented a problem when selecting a suitable engine.^[​19] The chosen 700 hp 5TDF engine was unreliable,^[​20] difficult to repair, and had a guaranteed lifespan similar to World War II designs.^[​21]