The European Data Relay System (EDRS) is a European satellite system designed to reduce time delays in the transmission of large quantities of data.

It will be a constellation of GEO satellites intended to relay information. The data relay satellites are placed in geostationary orbit to relay information to and from non-geostationary satellites, spacecraft, other vehicles and fixed Earth stations, which otherwise are not able to be in touch permanently with each other.

The system will allow almost full-time communication even with satellites in Low Earth orbit which often have a very reduced visibility from any ground station. It will make on-demand data available at the right place and at the right time, allowing for example rescue workers to see near-real-time satellite data of the crisis region where they are working in. The system is being developed as part of the ESA 'ARTES 7' programme.