EGNOS:
the European Geostationary Navigation Overlay Service, is a Satellite-Based Augmentation System (SBAS) that improves the accuracy and provides integrity to the GPS Signal over most of Europe.The EC owns and manages the EGNOS system. ESA is the EGNOS design agent under a delegation agreement with the EC.It is Europe's first venture into satellite navigation and a major stepping-stone towards Galileo, Europe's own global satellite navigation system for the future.It is Europe's first venture into satellite navigation and a major stepping-stone towards Galileo, Europe's own global satellite navigation system for the future.

ESSP SAS:
founded in 2009 by the Air navigation services providers from France (DGAC/DSNA), Germany (DFS), Italy (ENAV)), Portugal (NAV-P), Spain (Aena), Switzerland (skyguide) and UK (NATS) to act as service Provider for the EGNOS system, the European Geostationary Navigation Overlay Service.