Inflation targeting: the conventional analysis and an alternative model. This article has two aims: the first one is to present a formal model of the monetary policy identified generally as "inflation targeting policy", an instrument of intervention of the central bank, through the short run nominal interest rate. The second aim is to discuss and criticize the theoretical assumptions of the model specially the concepts of "natural rate of interest" and of potential product presented by the "augmented Philips curve"; and to present a more realistic control of inflation targeting which does not assume the hypotheses above, and in which inflation targeting is based on the control of real rate of interest.