Agriculture has a prominent role in phosphorus fluxes in France. The common interest is in using the resources in the most effective possible way to avoid environmental risks while preserving the economic competitiveness. The use of phosphorus is not regulated in France. Farmers are the ultimate decision-makers regarding P-flows toward agriculture. They need relevant and rather simple tools for decision. Stakeholders for decision support systems are numerous, from research to suppliers. To coordinate them, the COMIFER has been created in 1980. It promotes dialogue and applied research assessment to define rational procedure for decision. The COMIFER is an independent association; its members are split in 3 boards: public institutions, agricultural organizations and economic structures. It specificity is based on the publications provider realised with the consensus of all the members. The COMIFER manages several technical groups, one about P-K-Mg. For dissemination, the COMIFER organizes a congress every two years and proposes a web site where reference documents are downloadable. The P-K-Mg group deals with a scientific and technical monitoring of the state of the art and supports on-going works for the improvement of inputs management. He has published references and defined a simple and broadly used method for P management based on soil test interpretation. The Comifer has developed its cooperation with other structures closely related to fertility management at French national level. Now it also wishes to broaden its relationship at the international level to mutualize and harmonize the reflections, references and methods.