The Topeka shiner (Notropis topeka) is a plains stream minnow that was federally listed as an endangered species, effective January, 1999. For several years, efforts were made to determine its current range and habitat in Iowa with little success. Sampling in off-channel habitats led to improved collecting success in 1999; however, the fish was still primarily found in small numbers, and only a few sites proved to be spawning habitats. To aid in the search, I developed two quantitative models to identify suitable shiner habitat in the Des Moines Lobe geographic region. The general model was based on characteristics of all Topeka shiner sites, whereas the specific model was based on characteristics of "typical-quality" shiner sites. Geographic Information Systems (GIS) technology was used to measure landscape-level variables at locations of fish collections from in- and off-channel habitats made from 1970 to 1999. Classification trees were used to identify relationships between landscape variables and shiner habitat. Characteristics consistent in the models were: a general lack of forest/woody riparian cover, and frequently flooded soils (at least once every 2 years). These features are supported by field observations. The two models were applied within the GIS to develop maps identifying areas with characteristics similar to known "suitable" Topeka shiner habitat. These maps can be used to guide future search efforts and to identify places suitable for habitat improvement and reintroduction of Notropis topeka.