The soils and geology of the then metropolitan zone with particular regard to building foundations were discussed by Aitchison et al. (1954) in Bulletin 32 of the South Australian Department of Mines. The changes in urban development indicated above have now caused the situation to be reviewed. Since then a large amount of information has accumulated, so that the soil types may now be better defined, new ones created as necessary and the boundaries of their occurrence more precisely fixed. The area of the present study is about 460 square kilometres, much larger than the first survey, and embraces particularly some of the more recent building developments fringing the Adelaide Region. The publication is designed to assemble available information on the nature of the soils of the Adelaide region, to classify them into identifiable soil types and to show their distribution broadly on a soil map. Since the proper background is geological, an account is first given of the geology, physiography, and hydrology which, with the influence of climate, have controlled the development of the soil pattern. Finally, the relation of soils to engineering response and the problems ancillary to stability of buildings are discussed.