Fourteen species of gobies (Teleostei: Gobiidae), 12 of which were collected, were found living in association with seven “types” of alpheid prawn (Decapoda: Alpheidae) in the Seychelles, Western Indian Ocean. One new genus—Stonogobiops—and three new species—Stonogobiops dracula, Cryptocentrus aurora and C. wheeled—of prawn-associated goby are described. Full descriptions of the new genus and species, and shorter descriptions of the remaining species, are given; the genera Iotogobius Smith and Cryptocentrops Smith are synonymized with Cryptocentrus Ehrenberg. Aspects of the ecology of the prawn-associated gobies were studied. Species specificity between gobies and prawns varied considerably. The species present exhibited a marked degree of habitat segregation, and there were differences between species in nearest-neighbour burrow distances. A wide range of degrees of looseness of association between goby and prawn was also observed. The evolution of the symbiosis is discussed in the light of these observations.