This chapter examines the development of fisheries regulation in areas beyond national jurisdiction (ABNJ) from a constructivist approach. In doing so it provides important insights into how the construction of space is influenced by law making and institutional constraints, some of which reflect bias or imbalance in powers structures in international law. Many have defended law as a discreet and coherent discourse, but few have argued that it operates in isolation from material, social, or political discourse.1 Recognizing this wider context, constructivist approaches to international law show how social interaction and practice can create and give effect to law.2 In this tradition, law is viewed as a continuous communicative process wherein interactions between various actors, conditioned through institutional structures and practices, make law and generate compliance with it.3 As constructivism focuses on discursive, interactional practices, it is well-suited to bridging between law and other social science discourse.4 And engaging with discourse about materiality.5 Materiality here refers not simply to things as the mere object of legal relations (i.e. artifacts and their attributes), it also includes the meaning verst in such things which in turn can constitute social and cultural practices and identities in respect of those things.6 This is important, because we need to understand how law influences and is influenced by the material world. Constructivism offers a more complete account of how and why law is created than approaches which focus simply on law as a system of rules flowing from formal sources. This makes constructivism a valuable tool to examine how the current regime for the governance of ABNJ is developing and should develop. Here the development of a legal regime is closely bound up with wider material, social or political concerns, so it is important that we are sensitive to these.7