The Rhins of Galloway district lies in the south-west of Scotland and marks the termination of the Southern Uplands against the North Channel. This memoir and the accompanying 1:50 000 solid geology map provide detailed subdivision of the Ordovician and Silurian turbidite strata. The conclusions are of significance to the Southern Uplands terrane as a whole and also to its equivalents in Ireland and maritime Canada. Other major sections of the memoir discuss the syn- and post-tectonic intrusive rocks, the development of the late Palaeozoic Stranraer half-graben and the regional structural framework as deduced from geophysical data.