A military organization established in 1958 as the first US response to the Soviet launch of Sputnik. By 2001, DARPA had a budget of about US$2 billion and employed some 240 personnel, 140 of whom were technical staff. The latter are rotated every three to five years to provide fresh thinking and new perspectives. DARPA has maintained its founding principles of assuring a US lead in state-of-the-art technology for military capabilities and of avoiding technological surprises from adversaries.

The organization has changed its name three times since 1958. It was originally known as the Advanced Research Projects Agency (ARPA), adopting its present name in 1972. It reverted to the original ARPA in 1993, changing back again to DARPA in 1996.