The trilobite fauna of the Silurian successions of the Girvan area, Strathclyde Region, Scotland, is revised. Twenty eight genera (one new) belonging to the Scutelluidae, Illaenidae, Proetidae, Brachymetopidae, Aulacopleuridae, Harpetidae, Cheiruridae, Encrinuridae, Calymenidae, Phacopidae, Pterygometopidae, Lichidae and Odontopleuridae are represented, and include thirty nine named species (fifteen new), and twenty nine forms under open nomenclature. The fauna is interpreted as having occupied a shallow shelf environment. The distribution of trilobite species is compared with the shore-parallel brachiopod communities recognized in rocks of the same age in Wales and the Welsh Borderland.