Since a quarter of a century, several right-wing or populist right-wing parties have made a breakthrough in their national political system: the Front National in France, the FPÖ in Austria, the Progress Party in Norway and Denmark, the Danish People’s Party, the Slovak National Party, the Italian Social Movement — National Alliance, the Northern League, the Republikaner, the NPD and DVU in Germany, the Pim Fortun List and the Freedom Party in the Netherlands, Ataka in Bulgaria, the People’s Party of Great Romania, the Vlaams Belang and the National Front in Belgium, the Central Democratic Union in Switzerland, LAOS in Greece... In addition, a new political fact has emerged in recent years: in addition to the electoral and political progress observed by many of these parties, several far-right formations have taken up government responsibilities or supported governments from outside. In addition to the rich work on the developments of extreme right-wing parties, it was therefore necessary to analyse the conditions and consequences of this new situation. This is the approach of this book, which brings together contributions from the best experts on the issue. The focus is on the internal life and choices of these parties. Do they want to access power? Does this issue give rise to difficult debates? Is there a process of moderation when these formations return to the government? Do activists embrace this choice? Is the party sanctioned or strengthened in the following elections?... But it also focuses on the dimensions external to these formations. Do the themes of extreme right-wing parties impact on democratic parties? Is the extreme right’s contribution to certain issues that are dear to it? Can the extreme right be better stifled? ... Based on case studies and comparative approaches, the book provides novel answers to these contemporary questions.