The coordinated campaign to observe x-ray binaries sponsored by the IAU Commission 42 (Close Binary Stars) and Commission 44 (Astronomical Observations from Outside the Terrestrial Atmosphere) was initiated in January 1974 with Y. Kondo as its coordinator.

The main objectives of the campaign have been: (a) dissemination of information on satellite x-ray experiments and ground-based observing programs; (b) transmission of suggestions and recommendations from campaign participants; (c) designation of campaign dates for observation of specific objects. These functions have, in part, been performed through Campaign Circulars and Special Bulletins; the most recent, Circular No. 23, was issued a few weeks ago.