This contribution explores the reciprocal links between the organisational transformation of Western European Green parties and the access of some of these parties to national government participation. On the one hand, a series of hypotheses with regard to the possible link between prior organisational adaptation and eventual access to governmental participation are examined. On the other hand, the opposite question is addressed: that of the potential impact of governmental participation on further organisational adaptation. Following both a qualitative and Qualitative Comparative Analysis (QCA), one does ultimately identify a link between prior organisational adaptation and eventual access to government, but a much more indirect and contrasted link between governmental participation and further organisational adaptation.