The genus Cochliobolus (anamorphs Bipolaris, Curvularia) comprises many destructive plant pathogens that cause severe crop losses worldwide. The taxonomy of Cochliobolus is confused as frequent nomenclatural changes have occurred in the sexual and asexual states of species over the past 50 years. We provide an overview of these nomenclatural changes together with a morphological circumscription of the genus. Taxonomic notes and information about the life history of 55 species epithets of Cochliobolus listed in Index Fungorum are also given. Further information is given concerning the location of type cultures; availability of DNA sequence data derived from type cultures; mode of life; novel metabolite production; and use of Cochliobolus species in biocontrol. We provide a multilocus phylogenetic tree based on DNA sequence data derived from 25 ex-type and authentic cultures that shows the group as monophyletic. This paper represents the first comprehensive overview of Cochliobolus since 1987, including a summary of applications of species and molecular phylogenetic research. The 55 species of Cochliobolus are listed alphabetically, with synonyms, hosts and diseases, brief notes concerning taxonomic and phylogenetic research.