The textbook is aimed at students and educators who are engaged with citizen participation and political participation in Germany and other democracies. This includes, among other things, elections, citizen and referendum votes, as well as informal forms of participation. The book provides a comprehensive overview of the theoretical foundations of democracy, the institutional framework, and the relevant theories for explaining participation. It presents the main forms of political participation and citizen engagement individually, focusing on their theoretical and structural characteristics. Numerous empirical data and interpretations complement the discussions and provide a current picture of the participation landscape.