Comparative study has emerged as the new frontier of constitutional law scholarship as well as an important aspect of constitutional adjudication. Increasingly, jurists, scholars, and constitution drafters worldwide are accepting that 'we are all comparativists now'. And yet, despite this tremendous renaissance, the 'comparative' aspect of the enterprise, as a method and a project, remains under-theorized and blurry. Fundamental questions concerning the very meaning and purpose of comparative constitutional inquiry, and how it is to be undertaken, are seldom asked, let alone answered. In this path-breaking book, Ran Hirschl addresses this gap by charting the intellectual history and analytical underpinnings of comparative constitutional inquiry, probing the various types, aims, and methodologies of engagement with the constitutive laws of others through the ages, and exploring how and why comparative constitutional inquiry has been and ought to be pursued by academics and jurists worldwide.