Random amplified polymorphic DNAs (RAPDs) were used to examine accessions of vetiver (Vetiveria zizanioides (L.) Nash, Gramineae) from around the world. It appears that only one genotype, ‘Sunshine’, accounts for almost all the germplasm utilized. Screening of numerous accessions of vetiver revealed only a few nonfertile germlines. Analysis of V. zizanioides and other Vetiveria species, Chrysopogon fulvus (Spreng.) Chiov., C. gryllus (L.) Trin., Sorghum bicolour (L.) Moench., and S. halepense (L.) Pers., revealed that Vetiveria and Chrysopogon are not separable by their RAPDs. This lends support to merging the genus Vetiveria with Chrysopogon. The lack of genetic diversity in this important cultivated plant is a critical factor and additional, suitable germplasm must be collected and introduced into erosion control projects around the world.