n order to achieve these objectives, the "SI/GIRH" portal gathers information of national interest,relating to demarcationsand planning units basedon a principle ofparticipation. It alsoincludes the work ofSENAGUA and thecouncils in the planningframework (baselinemaps, practicalinformation). Thedynamic character of theinformation is assuredwith web services, ageographic viewer and acatalogue of metadatathat provides acomprehensivedescription of the dataand informationpresented. Theinformation madeavailable is based onmaterial produced bySENAGUA at central andlocal levels, applying theprinciple of subsidiarity,and also includesinformation available andproduced by all actors inthe sector,