During the summer of 1980 the Swedish ice-breakerYmerserved as a platform for an Arctic expedition carrying out an intense scientific program in the area from Franz Josefs Land westwards to Greenland, with emphasis on Svalbard and the surrounding seas. The geo-program included studies of the physical geography and Quaternary geology of Nordaust-landet and surrounding islands, and northeasternmost Greenland, with concentration on studies of glacial chronology and shore-line displacement, and special emphasis on the age of the ice-free areas. Marine geological and geophysical work was concentrated on transects across the shelf areas north of Svalbard, to the deep Arctic basin, and across the spreading zone between Svalbard and Greenland. It included dredging and coring, with heat flow measurements, and magnetic and seismic profiling. Glaciological work on small, low-lying and comparatively young ice-caps was carried out on some islands to the east and south of Nordaustlandet.