In 1956, she became an instructor in the Department of Social Sciences at New York City Community College. Next she served as a Research Assistant for the Council for Atomic Age Studies from 1961 to 1963. During the 1960s she worked with Alvin Weinberg at Oak Ridge National Laboratory (ORNL), where she conducted civil defense research related to the potential societal aftereffects of a nuclear weapons attack. She was the first social scientist at ORNL, where she was director of Science in Society Studies in the Oak Ridge Institute of Nuclear Studies from 1963–1966. After leaving ORNL she extended her interests and became known in community activist issues relating to corporate and government policies as they affect local communities.
She served as a chairman of the board of directors of the Council for Responsible Genetics from 1994–1996, is a trustee of Safety Systems, and was an editor for Sage Publications.
Currently Claire Nader is the President of the Shafeek Nader Trust for the Community Interest which seeks to advance the ability of citizens to participate and shape the quality of democracy in their community.
Claire Nader (September 1975). "The Need and Desirability for Problem-Focused Research on The Interrelationships Between Science and Technology and Values and Ethics" April 29, 1975. Also AAAS Interdisciplinary Workshop on the Interrelationships Between Science and Technology and Ethics and Values.
Claire Nader (1976). "The Energy of Waste and the Problem of Informed Choices," in Energy and the Environment Cost-Benefit Analysis, R.A. Karam and K.Z. Morgan, eds. Energy – An International Jr. New York: Pergamon Press, pp. 625–629.
Claire Nader (1977). "Comment" in Toxic Substances and Trade Secrecy, Technical Information Project, Washington, D.C., pp. 63–66.
Claire Nader (June 1978). "Cultural Factors: Unresolved Issues in the Conflict Between Individual Freedom and Social Control" New York Academy of Sciences Conference on Public Control of Environmental Health Hazards.