ESA/390 (Enterprise Systems Architecture/390) was introduced in September 1990 under the name Enterprise Systems Architecture/370 and was IBM's last 31-bit-address/32-bit-data mainframe computing design, copied by Amdahl, Hitachi, and Fujitsu among other competitors. It was the successor of System/370 Extended Architecture (S/370-XA) and, in turn, was succeeded by the 64-bit z/Architecture in 2000.