Klingberg's academic career and research papers earned him an international reputation in his field, and he was invited to take part in conferences by the World Health Organization. He was President of the European Teratology Society (1980–1982); and a co-founder and Chairman (1979–1981) of the International Clearinghouse for Birth Defects Monitoring Systems (ICBDMS). He also served as President of the International Steering Committee for the Seveso Accident (Italy) from 1976 to 1984. In 1981, he co-founded the International Federation of Teratology Societies and in 1982 at the congress of the International Epidemiological Association that was held in Edinburgh, Scotland, he was elected to its Council.