This study is a systematic and ethnobotanical treatment of the genus Ipomoea in Oaxaca, Mexico. This taxon merits deeper investigations because of present disorganization and disaccord in its classification on generic, subgeneric, and species levels. A second facet of the investigation involves an ethnobotanical survey on past and present nutritional, medicinal, and shamanic uses of these plants. The taxonomic study involved acquisition of herbarium materials from various sources with review of past descriptions and sectional organizations of the genus. Morphological.relationships were correlated with phytochemical data from collected plant materials from Oaxaca. A key to species, species descriptions, and sectional organization of the genus were constructed by these studies. A survey of plant uses was also compiled with reference to the relationships of these plants and their utilizations. / Master of Science