Carl-Ludwig Holtfrerich, now retired, was a professor of economics with a special focus on the U.S. economy and economic history at the John F. Kennedy Institute and the School of Business and Economics, both at Freie Universität Berlin. He continues to do research. Holtfrerich studied economics in Münster and Paris and earned his doctorate in 1971 from the Westphalian University of Münster. From 1971 to 1974 he worked as an adviser in the Foreign Trade Department of the Federation of German Industries. He was then an assistant professor of economics and economic history at Freie Universität Berlin. During this period he did research during the 1975–1976 academic year as a John F. Kennedy Fellow at the Center for European Studies at Harvard University. In October 1979 Holtfrerich completed the habilitation process at the School of Business and Economics at Freie Universität Berlin and accepted a position as professor at Johann Wolfgang Goethe-Universität in Frankfurt am Main. During the summer semester of 1980, he took up his work there as a professor of economic history. Three years later he accepted an appointment as professor at Freie Universität Berlin. He is a member of the Berlin-Brandenburg Academy of Sciences and Humanities and in 2015 completed an interdisciplinary research project funded by the Academy. It is entitled Staatsschulden: Ursachen, Wirkungen und Grenzen (Sovereign Debt: Causes, Effects, and Limitations).