The Southern African Plant Invaders Atlas (SAPIA) is a mapping project, launched in 1994, to collate data on the distribution, abundance and habitat types of invasive alien plants in southern Africa. The SAPIA database is a computerized catalogue of some 70 000 locality records of more than 600 naturalized alien plant species. The database incorporates records gathered by about 560 participants, since 1994, and from roadside surveys by the author since 1979. Among its many uses, SAPIA can assist biological control programmes, in several ways. Information on the geographical distributions and ecological requirements of invasive plants in their introduced range can ensure that biological control agents are brought from comparable habitats in their country of origin so as to optimize their chances of establishment and efficacy. Early detection of new invaders and new foci of spread allows implementation of biological control at an early stage of invasion with the potential to pre-empt severe problems. In the longer term, SAPIA can provide an historical record of the distribution of invasive plants and could be used to monitor their rate of expansion or contraction before and after biological control. This review is a report on the development of and recent progress with the SAPIA project.