The Impact of Internationalisation on the Swiss Decision-Making Process: A Quantitative Analysis of Legislative Acts, 1995-1999 Since the beginning of the 1980s, a growing number of studies have focused on the phenomenon of internationalisation. Yet, so far, the question of the impact of internationalisation on institutions and decision-making processes has largely been neglected. In this article we attempt to overcome this weakness by analysing how internationalisation has affected the Swiss decision-making system. To this end, we develop two research hypotheses. The first one deals with the effects of internationalisation on decision-making institutions, while the second one focuses on its impact on the degree of elite conflictuality. These hypotheses are tested on all legislative acts adopted by the Federal Assembly during the 1995-1999 legislative term and submitted to one of the three main direct democratic institutions (i.e. popular initiative, optional referendum, and obligatory referendum). Our findings show that, with the exception of cases of autonomous adaptation, legislative acts with a stronger international component arecharacterized by a weaker degree of pre-parliamentary consultation, as well as by a lower level of parliamentary conflict