This database has been developed as part of a Coordinated Research Project for the Development of a Database for Prompt Gamma-ray Neutron Activation Analysis sponsored by the International Atomic Energy Agency (IAEA). The data are derived from the isotopic measurements compiled in the Evaluated Nuclear Structure Data File (ENSDF), updated when necessary, and from elemental measurements performed at the Budapest Reactor Centre. The data were received from Richard B. Firestone (Lawrence Berkeley National Laboratory, USA). The program "Viewer" was developed by Viktor Zerkin (IAEA, NDS).