For the first time, a long-term global view of sea level change has become available to the ocean science community. The U.S. Navy's GEOSAT altimeter satellite has been measuring ocean surface topography with unprecedented precision since March 1985. GEOSAT represents a dramatic improvement over earlier observations from NASA's SEASAT mission primarily because of higher spatial resolution and longer temporal duration (3+ years vs. 3 months), as depicted on the cover of this issue. The measurement of sea level is an important variable in the determination of ocean circulation. A special session of the 1988 AGU Fall meeting will focus on studies of ocean circulation with the GEOSAT measurements.