Oftentimes, the need to build multidiscipline knowledge bases, oriented to policy scenarios, entails the involvement of stakeholders in manifold domains, with a juxtaposition of different languages whose semantics can hardly allow inter-domain transfers. A useful support for planning is the building up of durable IT-based interactive platforms, where it is possible to modify initial positions toward a semantic convergence. The present paper shows an area-based application of these tools, for the integrated distancemanagement of different forms of knowledge expressed by selected stakeholders about environmental planning issues, in order to build alternative development scenarios.