Height Modernization is a program within NOAA's National Geodetic Survey (NGS) that provides accurate height information by integrating Global Positioning System (GPS) technology with existing survey techniques. For years, GPS has been used to determine accurate positions (latitude and longitude), but now, by following Height Modernization standards, specifications and techniques, GPS can efficiently establish accurate elevations for all types of positioning and navigational needs. SCGS follows the (+-2 cm) vertical specifications for all GPS Height Modernization Projects.