We will describe the multi-modal browsing system, developed by us, that allow to add automatic speech recognition and text to speech functions to standard Internet browsers. The system is based on the temporal synchronization of HTML and VoiceXML documents. It was developed starting from a real Web application designed for a medical domain (i.e. an electronic patient record adopted in the oncology unit of an Italian ospital). We have recently introduced the possibility to define the multi-modal interaction by means of a single XML document. System evaluation is going to be carried out on data collected during the usage of the system in the hospital.