The Fleet Rehabilitation and Modernization (FRAM) program of the United States Navy extended the lives of World War II-era destroyers by shifting their mission from a surface attack role to that of a submarine hunter. The FRAM program also covered cruisers, aircraft carriers, submarines, amphibious ships, and auxiliaries. The United States Coast Guard also used this term in the 1980s for the modernization of its Hamilton-class cutters.

The program was started by Admiral Arleigh Burke as a response to estimates that the Soviet Navy would have a force of about 300 modern fast-attack submarines by 1957. The U.S. Navy was unable to produce quickly enough the destroyer escorts (redesignated as frigates after 1975) and other antisubmarine warfare ships to counter this threat, given its other priorities in new antiaircraft warfare frigates (redesignated as cruisers after 1975) and aircraft carriers, so Admiral Burke instead looked for ways to modify the existing World War II destroyer, which were rapidly becoming outdated anyway.

Burke oversaw preparation of a report to the House and Senate Appropriations Committees entitled "The Aging Fleet." The idea that became FRAM was only one of six recommendations of a special committee to address the poor material conditions of ships built during World War II. Those recommendations were, in order of preference:

United States Secretary of the Navy Thomas S. Gates embraced the last recommendation in a meeting with United States Secretary of Defense Neil Hosler McElroy on 11 November 1958.

A comparable program for the Royal Navy had provided modifications to 33 British War Emergency Programme destroyers, which were converted during 1949–1956 into 23 Type 15 first-rate antisubmarine warfare frigates and 10 Type 16 limited conversions, pending the construction of new Type 12 and Type 14 frigates.

Among the destroyers, conversion of the Gearing and Allen M. Sumner classes took precedence over the Fletcher and Benson classes. Destroyer conversions relied on experience with Fletcher-class destroyers modernized for transfer to Spain and Germany in 1957. The first two destroyers began FRAM in Boston, Massachusetts and Long Beach, California shipyards in March 1959.

In Navy slang, the modified destroyers were called "FRAM cans", "can" being a contraction of "tin can", the slang term for a destroyer or smaller destroyer escort.

In order to provide the ships with a credible antisubmarine weapon, the FRAM I upgrade for the Gearing class centered on the addition of AN/SQS-23 sonar and two new weapon systems, the ASROC rocket-assisted torpedo launcher with a range of one to five miles (not in FRAM II upgrades), and the DASH antisubmarine helicopter with a range of up to 22 miles (35 km). Both were armed with the new Mark 44 torpedo, which was also carried in the torpedo tubes of the warships. The ASROC could also launch a nuclear depth charge.