The Annotated Census lists and describes - on the basis of direct examination - all of the 560 located copies of the first and second editions of Copernicus' "De revolutionibus orbium coelestium that survive in North America, Europe, Asia, and Australia, as well as several copies of known provenance destroyed, stolen or otherwise lost in modern times. The entry for each copy lists its present location and describes particulars of its binding, size, and any shelf marks. A short history is given of the provenance of each copy, wherever possible with identification of owners and dates of ownership. Marginalia and interlinear notes are also indicated together with transcription and translation of the more important ones. The content of the more significant notes is discussed (with reference to the modern literature), analyses that sometimes develop into substantial essays. Numerous plates show examples of the handwriting of the major annotators. Appendices list the other works bound with "De revolutionibus, and prices at auction going back to the 18th century. The density and quality of the data provided about the copies make this a fascinating reference work not only for scholars interested in the history of astronomy but especially for all those interested in printing in the early modern period. The census will also provide an almost inexhaustible mine of information concerning the spread of ideas, scholarly networks, book collecting, and library development from the 17th to 20th centuries.