Future earth observation satellites call for GEO relay links to make their data immediately available to the user. While RF communication limits the GEO relay’s data rate to roughly 1 Gbps (Gigabit per second) laser communication will extend its capacity into the 10 Gbps range as is required for the future systems. Laser communication will be applied for EDRS, the European data GEO relay system. At first, it is foreseen to provide the RF LEO-to-GEO link with an additional laser communication channel, still limiting, of course, the GEO relay’s performance to the RF bottleneck. However besides the operational service, the EDRS laser terminals shall also demonstrate the performance of high data rate links for both, the inter-satellite link and the GEO-to-ground link.