The Swiss botanist Adolphe Tonduz worked in Costa Rica from 1889 to 1920. For 20 years he carried out important activities as a plant collector and the curator of the largest Costa Rican herbarium beginning at the Instituto Físico-Geográfico Nacional, and later at the National Museum. A large number of new species of Orchidaceae are found among his collections, most of which were published by the German taxonomist Rudolf Schlechter between 1906 and 1923. The type specimens of most of these species were lost during a fire in the Berlin herbarium in 1943. The typification of the orchid species described on the basis of collections by Tonduz is a fundamental step for correct interpretation of Schlechter's and other authors' taxonomic concepts, and this paper follows the path of similar works aimed at typifying the orchid species originally collected in Costa Rica by M. A. Brenes, R. E. Endrés, and C. Wercklé. Previously lectotypified and neotypified taxa are recorded, including their bibliographical references. Here we formally designate lectotypes for Brassavola scaposa, Bulbophyllum vinosum, Camaridium costaricense, C. dendrobioides, Chysis costaricensis, Cranichis nigrescens, Elleanthus tonduzii, Epidendrum abbreviatum, E. cardiophorum, E. henrici, E. octomerioides, E. pachycarpum, E. polychlamys, Goodyera ovatilabia, G. turrialbae, Habenaria endresiana, H. gymnadenioides, Maxillaria microphyton, M. pachyacron, Microstylis adolphii, M. microtoides, M. pandurata, M. tonduzii, Ornithocephalus tonduzii, Pittierella calcarata, Pleurothallis microtatantha, Scaphyglottis brachiata, Sobralia amparoae, Spiranthes tonduzii, Stelis aemula, S. conmixta, S. effusa, S. longicuspis, S. sarcodantha, Stenoptera costaricensis, and Tetragamestus gracilis. A new lectotypification is proposed for Epidendrum adolphi. Neotypes are designated for Cycnoches tonduzii and Epidendrum barbeyanum, and epitypes are designated for Pleurothallis microtatantha and Stelis aemula. Spiranthes tonduzii is not typified, as we did not have access to any extant materials for study.