The Mediterranean area exhibits very special characteristics. Severe extreme events occur regularly and the area has been identified as a climate "hot spot" in a recent study. The project CYPRIM studies the extreme rain events and the variation of their intensity or frequency under changed climate conditions. In a first step, the project characterises this systems using their large and medium scale environment. In a second step, using a high resolution climate scenario, some extreme rain events will be simulates using the model Meso-NH. The impact on the river discharge will be evaluated using the TOPMODEL and SIM hydrological models. The interest in the Mediterranean region under the framework of the CYPRIM project and other projects lead to the HyMeX initiative. A white book is currently being written in order to obtain a wide agreement of the scientific community on a field experiment and a project on intense rain events and regional impact of climate change.