The coding of medical records is one of the essential action to promote and develop a managerial practice within hospital. This article proposes to observe how this system has been thought and how it is put into action in order to make " what happens within hospitals " readable by managers. But this translation process is not self-evident. We focuses on the daily production of this information by following technicians in charge of coding. We observe how they transform medical records into bureaucratic and economic entities but also that they have to face to uncertainty especially concerning medical language. We show also that modalities of coding imply a singular conception of health care and participate to a managerial technique of government.
