The sedge genus Carex (tribe Cariceae) is one of the four biggest flowering plant genera worldwide (c. 2100 species), and the largest genus in temperate regions. Species play major ecological roles in many habitats, both as natives and weeds. Research indicates that generic limits should be broadened to include all genera currently in the tribe, including Uncinia. We are developing a species-level phylogeny for Carex. Molecular studies will cover c. 1360 species, examining 3-10 genes including two DNA barcoding regions already sequenced for hundreds of individuals in this group. A robust phylogeny of the genus is only half of the story; the other half is identifying lineages and assigning them valid names. Morphological and DNA data will be used to create a phylogenetically-based classification of Carex that is predictive, practical, and robust. A database of traits will be developed to test diversification patterns. All this will give a framework for future revisionary, evolutionary and ecological studies.