A survey of attempts to solve the critical hospital information flow problem, emphasizing PHS-funded computerization projects. No total hospital information system exists, although, since 1962, the VA has spent $6 million and PHS $10 million to develop them. Hospital business functions and diagnostic laboratories are automated successfully, often with hospitals' own funds, apart from the respective $2 million and $5 million from PHS. (A descriptive list of 41 computerized clinical laboratories is given.) Other PHS-funded hospital automation projects include: patient medical records, $4.5 million; logistics, $4.25 million; physiological monitoring (intensive care, operating room, cardiac catheterization), $6.5 million, apart from monitoring within cardiovascular care and research programs. This ignores Department of Defense and private inputs. Since hospitals are conglomerations of minimally related subsystems, success may be in networking discrete information subsystems that are not immediately compatible, rather than trying for a single overall system. (Prepared for the [Handbook of Biomedical Information] [Systems].) 40 pp. Ref.