This essay attempts to document the funds invested by the IDB and its counterparts and how the resources were used in the restricted field of protected areas in Brazil, during the period 1990-1999. For this purpose, all relevant documents regarding loans, technical cooperation and small projects approved or executed since 1990 were reviewed. The goal of the exercise was to fine-tune a search on the subject of protected areas, as defined by the World Commission on Protected Areas (WCPA) of the World Conservation Union (IUCN) and by the Brazilian legislation on the matter. On the basis of the results, the author discusses the viability of this kind of exercise, the perception of other institutions regarding IDB investments on biodiversity in Brazil and, briefly, the role of the IDB in assisting Brazil in the field of protected areas