From 1973 to 1994, de Groote was one of the Executive Directors of the International Monetary Fund (IMF) and from 1973 to 1991, one of the governors of the World Bank (IBRD).
From 1963 to 1992, he taught at the Faculty of Economics of the University of Namur (Belgium) as a professor, lecturing on subjects related to money and credit theories, monetary mechanisms and current international finance issues.
In July 1965, he was offered the position of financial advisor to the Belgian delegation at the OECD in Paris, where he headed a number of working groups involved in reviewing the first draft of multilateral agreements guaranteeing private investments.
During this time, he actively supported certain African representations, working to have the IMF and the World Bank enter into closer economic cooperation with them.
In addition to his work in the Congo, de Groote held the position of Director at the Research Department of the Belgian National Bank from April 1971 to November 1973.
Within the IMF, where he was active until 1994, de Groote represented a group of countries that included Czechoslovakia, or, as the case may be, the Czech Republic.