The project ISSEM is funded by the German Research Foundation (DFG). It aims to realize modelling system describing equally well ice-dynamic, as well as deformation processes of the solid Earth caused by the glacial-isostatische adjustment (GIA). For this, the ice model RIMBAY and the earth model VILMA are coupled, with a special focus on gravitationally self-consistent description of the sea-level variations. The main aim is to study the feedback between sea-level and ice dynamics changes on the time scale of a glacial cycle. ISSEM contributes to project DIEM.