The urban area of Almada County, in the Lisbon Metropolitan Area, is undergoing a very high rate of growth. However, there have been several examples of land development having taken place in areas with poor geotechnical characteristics, and a number of illegal constructions have disrupted the natural geomorphological evolution of the area, thus creating potential hazards for people and property. The current Almada Municipal Development Plan has not taken adequate account of geological and geotechnical information. Therefore, the authors have undertaken a research project to develop a set of engineering geological maps, as part of a spatial geoscientific database, to be offered online to potential users. This database also includes thousands of results from in situ and laboratory tests. The information is integrated into the socalled GEO-ALMADA Information System (SIGEO-ALMADA). Manipulation and analysis of the information in this system has allowed the derivation of several engineering geological maps in digital format (scale 1:10,000) that show geotechnical units, landslide susceptibility and erosion potential. Finally, an engineering geological zoning map was prepared, which shows the main geotechnical restrictions to urban development. This paper describes the methodology used to prepare and store the cartographic information, using
geographical information systems, as well as the main results obtained.