This book provides a comprehensive, interdisciplinary analysis of the transformation process of Western Balkan candidate countries as they move toward European Union (EU) accession. It systematically assesses the multidimensional nature of this transformation by critically evaluating the transformative potential of EU enlargement policy across key dimensions - governance, rule of law, democracy, economic alignment, environmental and digital modernisation, regional cooperation, and security challenges. Leading scholars and practitioners offer an evidence-based perspective on the impact, challenges, and limitations of the EU-driven transformation and valuable new resource material for scholars and researchers in EU studies, political science, international relations, and European integration.