This book offers a policy analysis of the emergence of the General Data Protection Regulation (GDPR) through the lens of John Kingdon's Multiple Streams Framework. Drawing on 32 expert interviews with key stakeholders-including EU institution representatives (such as trilogue negotiators), member states, industry leaders, NGOs, and journalists-the author provides a deep dive into the decision-making process behind the regulation. Additionally, the study examines 462 position papers from the EU Commission's consultation phases (2009-2011) to uncover the factors that shaped the adoption of the GDPR. At its core, this work explores the 'window of opportunity' that enabled the regulation's adoption.