The herpetofauna of the continental offshore islands of South Africa and Namibia is reviewed. Historical and recent records are discussed and the origin and affinities of the herpetofauna are considered. A total of 23 species has been recorded from 11 islands. The greatest diversity (16 species) occurs on the largest island, Robben Island in Table Bay. The commonest island species are Phyllodactylus porphyreus (seven islands) and Cordyliis cordyliis (four islands). All of the islands have rocky coastlines and are unsuitable for nesting sea turtles. The islands have been affected to different degrees by sea-level fluctuations associated with periods of glaciation. All were connected to the mainland during the last Glacial Maximum (16 000 BP). Human disturbance has occurred on all the islands and many species have been introduced. A number of islands have relict populations of some species, and these probably date from the time when the islands were connected to the mainland. No significant correlation exists between species richness and an island’s size or its distance from the mainland. This is attributed to the relatively small size of the islands, their depauperate herpetofaunas, and the habitat requirements of the species. The spotted gecko Pachydactylus maculatus grows to a much larger size on St Croix Island than on the adjacent mainland but gigantism does not occur in reptile populations on other islands.