The Copernicus Land Surface Temperature Monitoring, LSTM, mission will carry a high spatial-temporal resolution thermal infrared sensor to provide observations of land-surface temperature. The mission responds to priority requirements of the agricultural user community for improving sustainable agricultural productivity at field-scale in a world of increasing water scarcity and variability. Land-surface temperature measurements and derived evapotranspiration are key variables to understand and respond to climate variability, manage water resources for agricultural production, predict droughts and also to address land degradation, natural hazards such as fires and volcanoes, coastal and inland water management as well as urban heat island issues.