Professor L.H. Dupriez (1901-1986), founder of the Economic and Social Research Institute (IRES) and of the Department of Economics at the Catholic University of Louvain, was a leading figure in both the theory and the application of economics in Belgium during the 20th century. His personal archive, the Fonds Dupriez held at the IRES, is a mine of information on the history of economics and economic policy. The inventory (which lists 22 000 documents in 700 files) can be accessed online at http://dupriez.ires.ucl.ac.be.