This unique and important new book looks at how we interpret the evidence of change and stability in modern parties and party systems. Focusing primarily on processes of political adaptation and control, it also concerns how parties and party systems generate their own momentum and 'freeze' themselves into place. Amidst the widespread contemporary discussion of the challenge to modern democracy and the crisis of traditional forms of political representation, it offers a welcome emphasis on how party systems survive, and on how change, when it does occur, may be analysed and understood. The first part of the book deals with questions of persistence and change, and with the vulnerability and endurance of traditional parties. In the second part, attention shifts to the question of party organization, and to the ways in which the established parties are increasingly coming to invade the state, finding there a new source of privilege and a new means of ensuring their own survival. The third part of the book focuses on structures of competition in Western party systems, as well as on the problems associated with the consolidation of the new party systems in post-communist Europe. This is the first book to be entirely devoted to the question of party and party system change, and offers and essential guide to the understanding of this crucial theme. 'Peter Mair has produced a book that represents political science at its most erudite . . . It is a learned work based on wide reading. It is brimming with references to the contributions of other scholars.' Times Higher Education Supplement 'Building on several previously published essays of his, Mair has produced a precious little book. I particularly admire his ability to construct his argument with reference to the existing theories and to buttress it resorting to the available data. Moreover, he cleverly suggests different lines of interpretation and areas where new research is needed....there is a lot to be learned and to be utilised in Mair's analysis. The book is to be commended both for what it says and for what it suggests'. Gianfranco Pasquino, West European Politics 'With this volume Peter Mair brings together nearly a decade's worth of his work on European political parties. All but two chapters have been previously published, but in such a range of locations that the breadth and depth of his scholarship will likely have been underappreciated by all but the most dedicated students of European political parties. . . . The book has many strengths. It offers an important counterpoint to a literature that has become perhaps too focused on survey research and the behaviour of voters. The distinctions made between party system, party as organization and party in the electorate, while not completely novel, have been used with good effect to clarify the analysis of electoral change. Mair has drawn our attention, once again, to the intriguing notion of party autonomy vis-(-vis the state and civil society. The book is exceptionally clearly written and displays the author's encyclopedic knowledge of European political parties. Donald E. Blake, Canadian Journal of Political Science