Geospatial data and Geographic Information Systems (GIS) are critical infrastructure in the United States, vital for governance, economic activity, environmental management, and national security. Effective national-level coordination is essential to manage this complex ecosystem. The Federal Geographic Data Committee (FGDC) guides the National Spatial Data Infrastructure (NSDI), a nationwide framework of policies, standards, and partnerships for geospatial data. Key federal agencies, including the U.S. Geological Survey (USGS), National Oceanic and Atmospheric Administration (NOAA), and the Department of Homeland Security (DHS), serve as primary stewards of foundational national geospatial data. The National Geospatial Advisory Committee (NGAC) provides crucial non-federal perspectives to guide these federal efforts. This entry outlines the primary federal bodies, programs, and communities of practice that constitute the U.S. national geospatial enterprise, their interconnections, and the persistent challenges they face.
Spatial data infrastructure (SDI) is the infrastructure that facilitates the discovery, access, management, distribution, reuse, and preservation of digital geospatial resources. These resources may include maps, data, geospatial services, and tools. As cyberinfrastructures, SDIs are similar to other infrastructures, such as water supplies and transportation networks, since they play fundamental roles in many aspects of the society. These roles have become even more significant in today’s big data age, when a large volume of geospatial data and Web services are available. From a technological perspective, SDIs mainly consist of data, hardware, and software. However, a truly functional SDI also needs the efforts of people, supports from organizations, government policies, data and software standards, and many others. In this chapter, we will present the concepts and values of SDIs, as well as a brief history of SDI development in the U.S. We will also discuss the components of a typical SDI, and will specifically focus on three key components: geoportals, metadata, and search functions. Examples of the existing SDI implementations will also be discussed.