[8] Omenn worked with Christian B. Anfinsen at the National Institutes of Health from 1967-1969,[9] doing research as part of military service.
[10][8] Omenn was appointed as a White House Fellow in 1973-1974, under Presidents Richard Nixon and Gerald Ford.
He was one of two staff on Nixon's Project Independence, looking for ways to lessen America's dependence on imported oil.
[15] As of 1974 Omenn was first appointed to the National Cancer Advisory Board, as an alternate for Frank Press, Director of the Office of Science and Technology Policy.
Omenn's title was Assistant Director of Human Resources, Office of Science and Technology Policy.
[16] During 1977-1981, Omenn worked with the Carter administration, first as an assistant to Frank Press, the President's advisor on Science and Technology Policy, and then as Associate Director in the Office of Management and Budget.
[8] Omenn founded the Robert Wood Johnson Clinical Scholars Program at the University of Washington in 1975.
He served as principal investigator of the beta-Carotene and Retinol Efficacy Trial (CARET) seeking preventive agents against lung cancer and heart disease.
[18][19][20] In 1981, he was a visiting professor at the Woodrow Wilson School of Princeton University and the Brookings Institution's first Science, Technology, and Policy Fellow.
[23] From 1982-1988, Omen chaired the National Research Council's Committee on Science, Engineering and Public Policy.