An integrated GIS was developed as the core of a research project which provided the foundation for regional economic planning in a semiarid area in northern China. The GIS was composed of a regional geographical database and a collection of spatial models. The regional geographical database contained data sets from terrestrial-based sources including thematic maps and statistical records, and remotely sensed data. A series of spatial models has been developed by experts in various disciplines such as soil erosion, economics, rural development and arid-land management. These models were then implemented into the GIS and a series of thematic maps was produced. The results provided useful assistance for regional planning that aimed to balance demands from different land-use interest groups with the aim of achieving an optimum, environmentally sound economic development plan.