This chapter covers nine monocotyledonous families (Acoraceae to Cyperaceae), containing 917 species of aquatic macrophytes. For each species, the information is provided to a standardized format. Each entry describes the overall distribution, range area, origin within each ecozone where it is present (i.e., endemic to the ecozone, native to the ecozone and at least one other, or introduced to the ecozone via one or more anthropochorous vectors), rarity at global scale, global endangered status (as listed by the IUCN Red List), life form, ploidy state, speciation age, long-distance vectors of species distribution, and actual or potential uses. Some data are unavailable for some species, and the entries indicate where this is the case. The chapter also includes global distribution maps for every species and pictures of almost all species.