The invited lectures of the 1990 Predeal summer school cover some of the main achievements and perspectives in the field of the nuclear structure, from both the experimental and theoretical points of view. Among the main subjects are: reaching the nuclei far from stability, and the study of their structure and decay modes; properties of the nuclei at high spins and the physics of superdeformed nuclei; refined nuclear spectroscopy measurements; new developments in theoretical nuclear structure models; heavy fragment radioactivities.