[3] In 1951-53 he was vice consul and principal officer at the American consulate at Mérida, Yucatán, Mexico, and in 1953-55 he was second secretary and economic officer in the American embassy in Mexico, D.F..[1][3] 1957-59 he was Chief, Foreign Economic Section, Soviet Union and Eastern Europe Division, Bureau of Intelligence and Research of the Department of State.
[1][3] In 1967-74 he was Director of the Office of OECD, European Communities and Atlantic Political Economic Affairs, Bureau of European Affairs, in the Department of State in Washington, D.C.[1][3] In 1974-78 Katz was Deputy Chief of the United States Mission to the OECD in Paris, France, with the diplomatic rank of Minister Counselor.
[1][3][9] On July 9, 1981, President Reagan approved the nomination of Katz to be the Representative of the United States of America to the Organization for Economic Cooperation and Development, with the rank of Ambassador, a position that he held from August 1981 until May 31, 1984.
[8][10] At the International Organisation of Employers General Council on May 30, 2006, Katz was elected President, a position he held through 2008, leading an organization then comprising 146 members from around the world.
[7][5] In this role, and as Employer Member of the ILO Governing Body, he advocated for the global business community in international forums.
[6][10] He died in New York City after a short illness, age 86, and his funeral services were held at the Park Avenue Synagogue in Manhattan.