Nuclear level schemes and resonance parameters are of great interest for nuclear spectroscopy, for astrophysical models, thermonuclear calculations and for other applications. Parameters for nuclear levels of stable nuclei have been published in the Volumes I/16B, I/18A, B, C, and in I/19A1, A2. In the Volumes I/19A, B further data obtained from transfer reactions are presented. Volume I/19C contains the data of unstable nuclei far from the stability region which have been deduced from reactions other than transfer reactions (e.g. beta decay, spallation reactions, or inverse reactions). The data in these volumes should be considered as the most complete data collection for nuclear levels. The contents of the various volumes can be characterized in the following way: Data for unbound states (resonances) I/16B, C Low lying levels, neutron-induced resonances (I/16A contains general information on neutron physics) I/19A Highly excited levels above the low lying states, unbound states fromcharged-particle reactions (Z = 2 to 18 in I/19A1, Z = 19 to 83 in I/19A2) Data for bound states (stable nuclei) I/18A, B, C Low lying levels (Z = 2 to 36 in I/18A, Z = 37 to 62 in I/18B, Z = 63 to 100 in I/18C) In I/18A the theoretical methods of treating nuclei are summarized, in particular those for deformed nuclei. I/19B Excited levels from charged-particle reactions (Z = 3 to 36 in I/19B1, Z = 37 to 62 in I/19B2, Z = 63 to 99 in I/19B3)