The Global Positioning System (GPS) provides unprecedented potential for precise ground- and space-based positioning, timing, and navigation anywhere in the world. Extremely precise use of GPS, particularly for earth sciences applications, stems largely from activities of the International GPS Service (IGS). More than 200 organizations in 75 countries contribute daily to the IGS, which is dependent upon a cooperative global tracking network of over 300 GPS stations. Data are collected continuously and archived at distributed data centers. Analysis centers retrieve the data and produce the most accurate GPS data products available anywhere. IGS data and data products are made accessible to users, reflecting the organization's open data policy. The IGS, a scientific service of the International Association of Geodesy, is a highly successful international scientific federation and a model of international cooperation.