Astronomical directories are available as CDS Special Publications. They provide practical data that one seeks to have always at one’s disposal on astronomical organizations and related items of interest.

Over the years, these directories have proved to be very effective tools not only for improving national and international relationships in amateur and professional astronomy, but also for helping amateur astronomers, laypersons and public bodies to easily contact astronomical organizations as the need arises.

IDPAI 1989 (CDS Special Publication 12 - about 500 pages) will be the second edition of the International Directory of Professional Astronomical Institutions. It will gather more than 2600 entries from about 80 countries: professional astronomical observatories and institutions; organizations, universities, departments, groups or companies employing astronomers or researchers in astronomy; related entries of general interest: IAU adhering organizations, professional associations, funding organizations, academies, as well as bibliographical services, software producers, journals, publishers, manufacturers, dealers, etc.