This workshop is jointly organized by the Integrated Climate Data Center (ICDC), University of Hamburg, and the Max-Planck Institute for Meteorology (MPI-M), Hamburg, and co-sponsored by CliC, CliSAP, and ESA-CCI, aiming at both experts for sea-ice remote sensing and sea-ice modelling. New sensors and new algorithms have over the past few years allowed for sometimes significant progress in our ability to estimate sea-ice concentration and sea-ice thickness from space. In addition to existing sensors such as CryoSat-2, SMOS, AMSR2 and ASCAT, the launch of new sensors such as ICESat-2 and additional Sentinels will further widen our capabilities to ever more accurately measure the state of sea ice from satellites. Experts both for remote sensing and for large-scale modeling are invited to discuss and outline the most promising opportunities and best practices in the use of existing and future satellite sensors for the remote sensing of sea-ice concentration and thickness, and the use of such data in large-scale modeling applications. The workshop was held at Bundesstrasse 53, 20146 Hamburg, Germany. Report form the workshop, see http://icdc.cen.uni-hamburg.de/fileadmin/user_upload/ESA_Sea-Ice-ECV_Pha...