A catalogue containing the QSOs known with reasonable reliability from literature published before the end of 1981 has been compiled at the Asiago Observatory by C. Barbieri, M. Capaccioli, S. Cristiani, G. Nardon and A. Omizzolo, and will be published before the end of 1982 by the Memorie della Societá Astronomica Italiana.

The present release is an enlarged and updated version of that published by Barbieri et al. (1975). It provides basic data (names, equatorial and galactic coordinates at 1950.0, photometry, redshifts and information on radio emission, variability, morphology, presence of absorption lines, X-ray emission and finding charts) for 2004 QSOs, together with references, individual notes and cross reference tables. Two separate lists contain X-ray data for 271 QSOs (X-ray luminosity, optical-X and optical-radio spectral indexes) and absorption line data for 243 QSOs (absorption systems with their redshift, identified ions and wavelengths, spectral range, resolution and dispertion of the spectra).

The catalogue has been carefully checked for internal consistency and several discrepancies with the lists by Hewitt and Burbidge (1980) and by Véron and Véron (1975) have been resolved. The authors intend to provide a magnetic tape version of the catalogue to the Centre de Données Stellaires of the Strasbourg Observatory for distribution to the interested community.