The T-72 is a Soviet second-generation main battle tank that entered production in 1971. About 20,000 T-72 tanks were built, making it one of the most widely produced post–World War II tanks, second only to the T-54/55 family. The T-72 was widely exported and saw service in 40 countries and in numerous conflicts. Improved variants are still being built for export customers.
Uralvagonzavod produced the first prototype with a 125-mm gun and V-45K engine in 1968 as "Object 172". After intensive comparative testing with the T-64A, Object 172 was re-engineered in 1970 to deal with some minor problems. However, being only a "mobilization model", a serial production of Object 172 was not possible in peacetime. In an unclear political process decree number 326-113 was issued, which allowed the production of Object 172 in the Soviet Union from 1. January 1972 and freed Uralvagonzavod from the T-64A production.
The first batch was built as "Object 172M" and, after some modifications, it was tested again in 1973 and accepted into service as the "T-72" under Soviet ministry directive number 554-172 dated 7 August 1973.
At least some technical documentation on the T-72 is known to have been passed to the CIA by the Polish Colonel Ryszard Kuklinski between 1971 and 1982.