The work consists of two parts. In the first part, Thym provides an analysis of the general framework behind the EU rules on migration and the changing positions of the supranational institutions. Central to this part is a discussion on the significance of human rights and the case law of the Court of Justice. Several chapters identify general features guiding the interpretation and the administrative implementation of the common rulebook. In the second part of the book, Thym explores the policy design and the substance approached through a thematic, rather than a chronological, lens. These chapters provide a reliable inventory of the policy design, the legislation and judgments on all areas of European migration law.