As political systems around the world implement gender quotas to balance women and men's elected representation, new opportunities and expectations for how both men and women are recruited, selected, and promoted by political parties are created. This book demonstrates that gender quotas positively disrupt all levels of the political system: political office, political parties, and the careers of politicians. By focusing on the European Parliament and building upon evidence compiled from new data sources from 28 current and former EU member states, 1979-2022, it provides evidence that different quotas affect similar politicians in different ways.As quota implementation changes the pool of political aspirants that parties recruit from, the background characteristics that are prioritized in selecting candidates are enhanced to optimise the management of career trajectories at all levels of the system. Quotas are therefore not just effective for promoting gender parity, but also change the course of women's and men's political careers at subnational, national, and European levels of office. This volume should be seen as leading the conversation about the longterm changes that are achieved by implementing rules that promote inclusivity and increase institutional diversity. It is relevant to both academic and policy circles. Whereas existing literature has examined how, where, and why gender quotas arise, the book pushes forward conversations about the previously unexplored additional effects for quota implementation, from the perspective of the career progression of elected politicians.