Description: This article describes and, more importantly, identifies information systems which are either in existence or planned on the national, state, and local levels. It describes the data available on the national level from the National Center for Health Statistics, the 05ce of Research and Statistics of the Social Security Administration, the AMA, the AHA, etc. It also describes a number of state and local information systems and addresses itself to information systems for inpatient care, ambulatory care, and the needs and likely sources of data for PSRO’s.