Road intersections represent one of the most complex configurations encountered when traversing road networks. A high percentage of accidents occur at these locations. The introduction of wireless communications technologies onboard passenger vehicles is enabling the sharing of information and through it enhancing the situational awareness of vehicle drivers. In this paper the implementation of safety applications for cooperative vehicle systems is presented applied to road intersection safety. The system relies on three fundamental technologies: communications, localization and the modelling of the environment surrounding the subject vehicle. The paper centres in a case study, the priority crossing of an Emergency Service Vehicle at an intersection. An analysis of the issues identified during the implementation and testing is included. The implementation represents an instance of the architecture developed for cooperative vehicles applications as part of the European project, SAFESPOT.