Prescription errors are a major source of preventable adverse drug events. Computerized prescribing (CP) which screens physicians' order for mistakes, drug-allergy, drug-disease, drug-laboratory and drug-drug interactions can prevent many of these errors and improve quality of care. However, computerized systems are often time-consuming, difficult to handle, and may create their own mistakes. Following the introduction of CP on an internal medicine ward, we administered a questionnaire to evaluate physicians' opinions about the new system. The survey assessed computer literacy, ease of using CP, effects on time management, opinion of users regarding error prevention, and usefulness of the information provided. Opinions were generally favorable; most users felt that CP makes their work more accurate, reduces errors, is easy to learn and to use, and provides important and useful information. Physicians were most critical of equipment failure and drugs and dosages not included in the CP program, a result of rapid development of the system. Errors resulting from the use of CP were considered minimal. Comparison of physicians, with and without previous experience with computer work, as well as local and foreign graduates, revealed minor differences. But once physicians learn to work with a well-organized CP system and computerized work stations, they appreciate the order, safety and knowledge they provide.