This article deals with the nature and the evolution of the relationships between the Belgian French-speaking Green party Ecolo and the new social movements in Wallonia and Brussels, from the larger identified sectors of these movements (environment, third-world, peace, anti-nuclear, women) to various other movements. To start with, the status of these movements in the emergence of the Greenparty is scrutinised. Then, on the basis of a survey conducted amongst members of the party elite (elected representatives and cadres), different modalities of the party/movements links are analysed: joint activism, selective communication channels between the elites, structural links. The bottom line is that, altogether, the links are tighter than one might expect, but that the Green party new social movements linkage remains ambiguous in many respects.