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Regardless of when the digital revolution began, profound changes have occurred during the past 50 years in the way spatial data are collected, stored, manipulated, and used. In years past, maps were made using plane table methods and other manual surveying techniques. But, mapping and automation of spatial data collection has progressed enormously since the 1950s and 1960s, when photogrammetric mapping techniques greatly simplified design activities for the U.S. interstate highway system. Similarly, the electronic calculator replaced the slide rule in the 1970s and surveyors have been using electronic total stations since the early 1980s. During the past 20 years, the global positioning system (GPS), geographic information systems (GISs), and the World Wide Web (WWW) have joined the technological onslaught, so that now spatial data can be characterized as digital and three-dimensional (3-D). Regretfully, development and implementation of the conceptual models used to handle spatial data have not kept pace. But a comprehensive 3-D global spatial data model (GSDM) has been defined which accommodates new technology existing practices, and any location on Earth or within the birdcage of orbiting GPS satellites. Spatial data users in many disciplines all over the world stand to benefit from adopting and using a comprehensive standard 3-D model.