Clinical laboratory testing accounts for over eight percent of health care expenditures in the U.S. The use of computer technology has led to improved analytical instrumentation as well as to data acquisition and data management systems. Clinical laboratory, information systems have demonstrated their ability to reduce clerical and technical labor costs while providing more accurate and readable reports to the physician. The majority of systems currently operating were developed by commercial systems houses, and costs can range from under $100 000 to over $1 000 000. A major challenge is the use of such systems for the collection and analysis of large databases for clinical research.