Molecular markers have been developed for use in genetic diversity studies within the genus Ribes. Random amplified polymorphic DNAs (RAPDs) were utilized with 21 genotypes of the blackcurrant, R. nigrum. All accessions were uniquely distinguished, including sister seedlings. Accessions of Ribes subgen. Ribesia (red/whitecurrant) were studied with inter-simple-sequence repeats (ISSRs). The genetic relatedness of three wild species to adapted germplasm reflected their use in redcurrant breeding programmes. Genetic variation in the gooseberry, R. grossularia subgen. Grossularia [R. uva-crispa], germplasm was examined using RAPD, ISSR and amplified fragment length polymorphisms (AFLPs). AFLP markers separated closely related genotypes which were indistinguishable with RAPDs or ISSRs. RAPD markers were also used to identify mislabelled plants in field trials. The implications for Ribes breeding and for genetic fingerprinting of varieties were considered.