The Taxonomic Name Resolution Service (TNRS) is a tool for the computer-assisted standardization of plant scientific names. The TNRS corrects spelling errors and alternative spellings to a standard list of names, and converts out of date names (synonyms) to the current accepted name. The TNRS can process many names at once, saving hours of tedious and error-prone manual name correction. For names that cannot be resolved automatically, the TNRS present a list of possibilities and provides tools for researching and selecting the preferred name. Taxonomic standardization is a major challenge for virtually every field of plant biology. Ecological studies encompassing large numbers of species, conservation decisions based on data from multiple sources, molecular analyses linking sequence data to organisms all require accurate species names, and the correct matching of names among data sets. Misspelled or out-of-date, synonymous names can be a major source of error. Large, collaborative databases such as GBIF, SpeciesLink, VegBank, SALVIAS, TraitNet, and GenBank are plagued by taxonomic problems, with up to 30% of names unmatched to any published name. Even among published names, 5% to 20% are synonymous. Despite the growing availability of digitized sources of names - www.ipni.org, www.globalnames.org, www.tropicos.org, www.ubio.org - and taxonomic opinion - www.tropicos.org, www.theplantlist.org -, taxonomic standardization remains an error-prone and largely manual process. The need for an automated name resolution service has never been greater.