With the onset of the
Eisenhower administration, Fowler returned to his private law practice and served on the
Democratic Advisory Council, which helped outline party positions on many issues. Fowler served as a member of the Commission on Money and Credit from 1958 to 1961, and of the National Committee on Government Finance of the
Brookings Institution from 1960 to 1961. He was a Trustee of Roanoke College and of the Funds in the
Episcopal Diocese of Virginia. He served as the Under Secretary of the Treasury, from February 3, 1961, until April 10, 1964. He spent was the most of his time at Treasury working on passage of the administration's tax program, which included an $11.5 billion tax cut. He then he returned to private law practice as senior member of the Washington firm of Fowler, Leva, Hawes and Symington. When
C. Douglas Dillon resigned, Fowler served as
Secretary of the Treasury from April 1, 1965, to December 20, 1968, Fowler was known for his loyalty to Johnson throughout the administration's ups and downs. He was described as having "a ruddy face, southern charm and a conservative outlook". The major problems facing Fowler were inflation and the balance of payments deficit. In August 1967, Fowler began the fight for a 10 percent tax surcharge and saw the proposal passed by a House–Senate conference in June 1968. In the debate over the balance of payments deficit, Fowler was a proponent of the "go-slow" approach. Fowler organized a two-tier system for gold in 1968, and participated in the 1967–68 international agreements, which created a new international monetary reserve system called "
special drawing rights". He proposed (1967) a seminar (taken up by then
Chancellor of the Exchequer James Callaghan) of financial officials from rich countries, the forerunner of the
Group of Five. He also ended silver coinage in the United States. After leaving the Treasury Department, Fowler became a partner with
Goldman Sachs in
New York City,
New York. ==Death==