The FLEX mission has been in preparation for several years. In preliminary studies, remote sensing data on solar-induced chlorophyll fluorescence (SIF) were collected on the ground and from the air. References to freely available data and campaign reports are linked under Campaigns. Tools for analyzing SIF data and FLEX data are under development. An overview is compiled in Tools. Projects contains an overview of ongoing and completed research projects related to the FLEX mission. Publications contains a thematically sorted overview of scientific studies on SIF.