This article discusses about a recent procedure in health care studies, the comparison as a methodology of analysis. The different analytical currents refer to a particular method of understanding health-disease process. They are: functionalism, the historical-materialism and the new currents. Their phylosophical and sociological basis, concepts, analysis instruments and purposes are showed here by a review of the principal works from representative authors as Navarro, Terris, Roemer, Fry, Illich, Capra and others. The paper suggests that comparative analysis can take two directions: the first is a operational approach for analysing the concrete situations of health's service organization, the second, a more conceptual one, aimed at identifying critical questions and international tendencies in health's systems. The recent discussion search for the overcoming of these dichotomies toward the progress of the production of knowledge and its efects in health's services organization.