The quality criteria of guidelines are identified. Taking these criteria into account we have built a platform to improve computable guideline effectiveness and facilitate their production. Our implementation is based on the GLIF Model (GuideLine Interchange Format). We have designed software components to edit, test, index, perform and present guidelines in a user-friendly Web architecture. These components are based on XML specifications in order to preserve their shareability and their re-usability. Several guidelines have been developed using our approach. We discuss the advantages of such an implementation and future evolutions so as to improve guideline integration within the clinician's workflow.