Clinical investigations (CIs) are carried out to demonstrate safety and efficacy of new Medical Devices (MDs). The presence of many stakeholders participating in CIs makes it necessary to develop a common standard language to achieve semantic interoperability among systems and organizations. In Italy the National Research Council is carrying out a project supported by Ministry of Health aiming to develop an information system (MEDIS) that manages MD clinical investigations. In order to develop a flexible and interoperable system, MEDIS design has been based on the application of HL7 (Health Level 7) v.3 standards. This paper presents the results of the MEDIS design: the MD DAM based on HL7 RIM.