The HyMeX database aims at documenting, storing and distributing the data produced or used by the project community. It will manage past and recent geophysical in situ observations, satellite products, model ouputs, questionnaire data … . In order to simulate the exchange of information and collaboration between researchers from different disciplines or using different tools, the database system provides a detailed description of the products and uses standardized formats whenever possible. The database is being developed jointly by SEDOO, OMP, Toulouse and ESPRI, IPSL, Paris.