Clinical practice guidelines are being touted as a cure for the tension between health care cost and quality. Rather than being just a means of controlling clinicians, guidelines also offer the chance to improve the quality of care by reducing practice variation and adherence to standards of good care. To be operationalized via computers, guidelines must be accepted by the clinicians, who must fully intend to follow them. They must be timely and use available data with minimal additional data entry by clinicians. Finally, they should have a measurable effect and be shown to improve care processes and/or outcomes.