'Under One Sky is primarily a publication celebrating the centenary of the IAU and only secondarily a serious contribution to the organizational history of the astronomical sciences. On the other hand, it includes a wealth of biographical and other information as well as several chapters that will be of interest to historians of modern astronomy.' Helge Kragh, Journal for the History of Astronomy
Part I. Centenary Celebration Session. 1. 100 years of astronomy, astrophysics and cosmology M. Longair; 2. Reflections on 100 years of IAU C. Cesarsky; Part II. Reminiscences from Past IAU Presidents; Part II. Reminiscences from Past IAU Presidents; Part III. Reminiscences from Past IAU General Secretaries; Part IV. The IAU and its History; Part V. The IAU and its Relation to Diverse Geographical Regions of the World; Part VI. IAU Structures and Organization; Part VII. Astronomical Publishing; Part VIII. The International School for Young Astronomers; Education and Outreach; Part IX. Some Miscellaneous Topics in Astronomical History; Part X. The IAU in the Future.