ABSTRACT
The increasing globalisation of national economies and the need for concerted international efforts in the environmental field are creating a demand for transnational spatial data. Three key issues-technology, disciplinary aspects, and organisation-control the ways that spatial data from different sources can be successfully brought together for a common good. The first issue, technology, addresses the fact that there are many different ways of storing and transmitting spatial data in electronic form. To meet demands for improving the technical aspects of data exchange there have been calls for the establishment of transnational and even global spatial data infrastructures and spatial data standards to improve system interoperability (see, for example, McKee, 1996; Schell, 1995). The second issue, disciplinary aspects, addresses the problems arising from the fact that related sciences and technical methods do not necessarily describe or recognise the same spatial phenomena in the same way; these problems are being addressed by the development of international standards for data description. With respect to transnational spatial data, the essential issue is the recognition that most spatial data are collected by national rather than supranational agencies thereby reflecting local and national rather than wider regional or global concerns. For all these reasons a great deal of non-technical effort is often required to obtain and to transform national data sets on similar or related themes into spatial databases suitable for international applications. In the process, a wide range of legal and institutional issues may have to be resolved in addition to the technical and disciplinary problems involved.
