The Shipibo system of ethnobiological classification is found to be generally in accordance with the cross-cultural generalizations of Brent Berlin and Cecil H. Brown, among others, specifically with regard to the development and organization of major categories, such as life-forms. Nevertheless, the Shipibo system also presents certain special problems for the cross-cultural study of ethnobiological taxonomies, displaying unexpected intermediate zoological ranks. Finally, details of Shipibo categorization of plants and animals, including the naming of categories, suggest that human intervention in taxonomic systems needs to be considered beyond the mere perception of apparent characteristics of the items classified.