ARESA is a non-profit organization, clustering more than a hundred companies active in Clinical and Pharmaceutical Research in the Walloon Region. The cluster brings together the operators needed to the different stages of clinical research within a framework strictly delimited by the different relevant national or international authorities. The strategy of the Clinical Research cluster is to develop the complementarity of these research operators by combining their assets and by fostering relationships of trust and habits of working together. The networking approach allows to meet criteria of speed (reaction in line with the needs of the sector), quality criteria and marketing criteria (to be visible and attractive).