In the past 20 years, a number of acronyms have been used to describe radiographic image management functions to achieve flimless radiology. These functions include acquisition, networking, workstation displays, archiving, image data compression, and patient data information management. The PACS acronym (picture archiving and communication system) was proposed by Dr. Judith Prewitt (at NIH when proposed) and freely used in the first PACS Conference (Duerinckx, 1982).! An alternative acronym proposed and used was image management and communication (system), IMAC, network, originated by Seong K. Mun,2 Georgetown University. An acronym of IDS (integrated diagnostic system) was proposedby de Valk.3 These changing acronyms represented the levels of difficulty at various times in the technology for implementing a radiology imaging management system. Yet, the most commonly used acronym remains PACS. In the early 1980's, archiving and communication functions were difficult to implement due to the status of archiving and communications technology. There is a wealth ofpublished material regarding PACS. One ofthe leading resources is the Proceedings ofthe International Society for Optical Engineering (SPIE) workshop on PACS Design and Evaluation. This workshop has been held every year in February during the SPIE Medical Imaging yearly conference. Papers for the SPIE meeting are selected and accepted based upon a submitted abstract. Posters are selected from the same set of submitted papers (examples48). The SPIE Proceedings are papers that are prepared by authors, providing the latest PACS implementation. An outstanding source of PACS papers is the Journal ofDigital Imaging, the Editor being Roger A. Bauman, M.D. This is the officialjoumal of the Society for Computer Applications in Radiology (SCAR). It begin publication in 1988 and is indexed in the Index Medicus. Several books are available dedicated to PACS. Among these books are the following: (a) J. P. J. de Valk (ed), Integrated Diagnostic Imaging, Elsevier Science Publishers, The Netherlands (1992); (b) H. K. Huang, PACS, VCH Publishers, N.Y. (1996); and (c) E. L. Siegal, R.M. Kolodner, Filmiess Radiology, Springer Medicine, 1998. In addition, the Journal of Radiology and the American Journal of Roentgenology often publish peer-reviewed papers on aspects of PACS. Like many other computer applications in radiology, there is no lack of publication sources available for good PACS papers. Sources available for a PACS history are extensive. A cursory estimate is that over 3,000 published articles exist and the classification of these published articles and papers is difficult. For purposes of this history, the segmentation is shown in Figure 1 . Also, cited papers are limited to one single category. Each division in Figure 1 will be limited to but a few cited references. This does not mean that the many other published papers that are not cited, are considered second-class papers. And, the selection and classification ofpapers was the sole responsibility of the author of this paper. A true history of PACS requires a group of experts selecting the key papers to be cited.9 It can be argued that a PACS history over the past twenty years will be difficult to accomplish due to changing technology (always improving), serious modifications to the health care system, changes in the imaging systems used by radiologists in providing services to the practicing physician and the patient, and the many vendor changes.