Book excerpt: Membership of political parties is diverse. Not everyone participates and those who do, do not participate in the same way. This book engages with the debate over the significance and future of political parties as membership organisations and presents the first broad comparative analysis of party membership and activism. It is based on membership surveys which have been administered, gathered and collated by a group of prominent party scholars from across Europe, Canada and Israel. Utilizing this rich data source together with the insights of party scholars, the book investigates what party membership means in advanced industrial democracies. In doing so, it provides a clearer picture of who joins political parties, why they do it, the character of their political activism, how they engage with their parties, and what opinions they hold. This text will be of interest to scholars and students of comparative politics, particularly to those interested in representation, participation, political parties and elections.