Nuclear structure physics at GSI - challenges and perspectives

The present situation as well the perspectives for the exploration of exotic regions near and at the drip lines as well as at the upper end of the chart of nuclides will be discussed in the frame of recent experimental results and future plans. Selected issues are superheavy nuclei, light halo systems, nuclear skins, and shells far-off stability. Key experimental developments are in flight separation and single-atom decay studies, ultra sensitive gamma-spectroscopy, reaction studies at relativistic energies in complete kinematics, and mass measurements of highest precision in heavy ion storage rings. Characteristic examples of experimental results from superheavy elements, halo and skin-nuclei, and masses in the neutron deficient region below lead will be discussed in the light of currently used theories. A brief outlook on next generation facilities for structure research including high current heavy-ion accelerators and new experimental developments such as reaction studies in storage rings with high resolution and physics using low-energy heavy-ion-electron colliders will be given. (author)