This symposium was held May 18–19 as part of the International Association of Hydrological Sciences Third Scientific Assembly in Baltimore, Md. Sponsored by the International Committee on Remote Sensing and Data Transmission (ICRSDT), the symposium was well attended, with some sessions having over 100 participants. Five sessions were held, covering the topics of large-scale processes; evapotranspiration; precipitation; ice, snow, and climate; and remote sensing, with a total of 19 papers presented. All authors were present, and all papers were prepublished as IAHS Publication 186, price $40. In addition, a poster paper session was held.