Evapotranspiration (ET) is a key component of the energy and water cycles over global land surface. But, it is difficult to accurately estimate ET because of its strong dynamics, diffusiveness, and heavy dependence on land cover conditions. Lots of resources have been allocated for ET observations at various ecosystems over the last two decades, however they are still not comparable to those for precipitation and runoff monitoring. Although the research effort in ET has been substantial in the past, the tools produced for industry and decision makers are not always sufficient. This session aims to solicit recent advances in ET observations, estimation methods, and applications, at multiple temporal and spatial scales. Advancements might include the development of new ET models and remote sensing algorithms and applications, integration research to demonstrate new innovative application of ET research, as well as field and lab experiments to improve our understanding of ET processes.