ABSTRACT During the first half of the nineteenth century, while Georges Cuvier ruled over natural history and the Muséum d’Histoire Naturelle (MHN) was at its institutional acme, a French banker and industrialist with a Swiss family background, Benjamin Delessert, was developing an important botanical museum in Paris. His private collection included both a rich botanical library and a massive herbarium: the close integration of these two dimensions, together with the magnanimity of Delessert’s patronage, contributed to making this private institution a (...) worthy rival to the powerful and state-funded MHN. Delessert’s museum had the favor of both professional and amateur naturalists. Knowledgeable and dedicated assistants (Antoine Guillemin and Antoine Lasègue) curated the collections. Moreover, Delessert was an intimate friend of the Genevan botanist Augustin-Pyramus de Candolle. Although Delessert’s herbarium followed the Linnaean order, the Delessert Botanical Museum (DBM) contributed to the development of Candolle’s natural system, especially through the publication of costly volumes of engravings, the Icones selectae plantarum rariorum. This essay draws together the main steps in the evolution of Delessert’s collections, stressing the interdependency between books and dried plants. It focuses on the DBM as a case of cooperation between institutional and amateur expertise, private and public collections, and field collectors and cabinet naturalists. (shrink)