In response to well documented requirements for regional and continental scale digital elevation models (DEM’s), the staff at the US Geological Survey’s EROS Data Center is developing global digital elevation data with a horizontal grid spacing of 30-arc seconds (approximately I kilometer). The DEM’s are generated from several topographic data sources, each requiring specific processing methodologies and quality assurance procedures. The continent of Africa serves as a representative example for a description of the techniques used in development of the 1-kilometer elevation models. Digital Chart of the World (DCW), a vector cartographic data set based on the 1: 1,000,000 Operational Navigation Charts, was the source data for roughly one-half of the Africa DEM. The hypsography, drainage, and coastline data from the DCW were processed with a surface gridding program. The other half of the Africa DEM was generated from information derived from Digital Terrain Elevation Data (I) TED), a raster topographic data base with a horizontal grid spacing of 3-arc seconds (approximately 90 meters) produced by the Defense Mapping Agency. The DTED data were generalized to 30-arc seconds with a scheme that retains the topographic breaklines (streams and ridges) from the full resolution data in the reduced resolution representation. Because of differences in topographic detail and accuracy along the irregular boundary between the two data sources, the merging procedure included blending techniques to minimize the discrepancies. The resulting DEM has an absolute vertical accuracy of better than 100 meters (root mean square error).