The principal objective of this article is to provide a general overview of the historical development and the political performance of Green parties in Western Europe. The analysis first examines the duration of Green parties' existence before entering national parliaments. Secondly, their electoral performance and their parliamentary duration are measured cross-nationally. It is argued that the Greens in Western Europe have stabilised their parliamentary as well as their electoral performance, although their electoral results remained rather marginal. Based on the theoretical and empirical assumptions of the 'party-lifespan' approach, the article offers a preliminary classification of Green parties' political impact in government.