This chapter offers two contributions to this collection. Its first part is dedicated to a conceptual overview of the nature and use of legal transplants. A concept central to comparative law, this is concerned with the movement of legal doctrines between legal systems in all fields of law. An overview of some of the central studies of legal transplants is ordered thematically, providing typologies of existing analyses of the nature of legal transplants sorted under several categories that range from the type of influence of foreign doctrines, through the motivations of such transplants, to the outcome of a transplant. This part also emphasises that the transplantation process is an ongoing, multi-participant exercise. The second part complements Caffera, Momberg and Morales’ chapter in this volume, which is concerned with legal transplantation in private law. In this part, I offer an example of the ways in which public law doctrines emerge and are subsequently transplanted into domestic systems, sometimes with limited, if any, attention to the particularities of public law concepts as they apply in different systems. The analysis of the movement of the ‘margin-of-appreciation’ doctrine is but one example of the highly complex nature of the movement of law around the world.