In a tribute to the work and writings of Professor John Bell, leading scholars present essays on factors affecting the course of ‘legal development’ in common law and civilian systems. This introductory chapter draws on their essays and John Bell’s scholarship to reflect on what is distinctive about comparative legal research. It shows how a comparative enquiry expands the boundaries of the law’s domain beyond ‘black-letter’ legal knowledge to embrace the reasons and context for legal development. It reminds us that a comparative law enquiry includes looking at the law’s roots in society, that is, at the law both in action and in the books, the legal institutions, legal cultures, and the extra-legal environment. References to the authors’ case studies in tort, contract, legal history and judicial studies illustrate the discussion of the key features of comparative law research.