From Economic to Behavioural Analysis of International Law: What Have We Learned So Far?

International law was one of the last areas of law to be analysed by economic theory. Economic analysis of international law was also late in turning from rational choice theory to cognitive-behavioural science. This chapter highlights the different ways in which behavioural insights can be and are used in international theory and practice. When behavioural science is applied within the state-to-state context, law-making and compliance as governance mechanisms need to be re-theorized. Yet, the cognitive-behavioural approach faces challenges in respect of the unit of analysis as well as the hitherto strict focus on methodological individualism. The chapter suggests some ways forward.