ABSTRACT
Approximately 85% of the European Community's population lives and works in urban areas (Eurostat 1993). This spatial concentration of human activity has very significant environmental and economic impacts, both within and beyond the immediate urban fabric, arising from the need to service it with appropriate physical resources (e.g. energy, food and water) and to dispose of the resultant waste products. Despite this, basic information on urban areas-such as their location, physical extent, human population and rate of growth -is often dated, inaccurate or imply non-existent. In this context, the potential for satellite remote sensing systems to deliver timely, consistent and spatially comprehensive data sets seems clear. In practice, however, there has been a marked disparity between the apparent promise and delivered performance (Barnsley et al. 1989, Kutsch-Lojenga and Meuldijk 1993, Orsi 1993). To ensure that greater value is deri ved from satellite remote sensing in the future, it is instructive to examine the causes of this disparity.
