Because of the inadequacy of existing biodiversity distribution data, surrogate measures for regional biodiversity have long been used in conservation area selection. These measures include species and environmental data. However, the assumed relationship between surrogate measures and regional biodiversity has seldom been demonstrated. This study uses species and environmental surrogates (vegetation and landtypes) in selecting areas for conservation in the Limpopo Province of South Africa. The success of these measures in capturing known regional biodiversity is evaluated, as well as their success at identifying areas containing threatened, rare and endemic non-target biodiversity features. The effects of size, scale and quality of databases are also evaluated. There is a trade-off between representing non-target biodiversity features (especially rare, threatened and endemic features) and land-use efficiency. The trade-off between efficiency and representation suggests that many important conservation areas identified will rely on off-reserve management rather than formal protection. Furthermore, the results suggest that the IUCN-recommended national conservation targets of 10 % are inadequate.Key words: conservation, environmental surrogate, landtypes