"The first section of this essay defines a few key terms and provides some historical background on the relationship between international law and international relations. The second section discusses the major theoretical approaches, from those that highlight material incentives to those that rest on more ideational foundations. The third section discusses international law development – concepts of legalization, judicialization, constitutionalization, and global administrative law. The fourth section reviews theories and empirical studies of compliance with public international law. The final section concludes that theory has become less compartmentalized by “school” and empirical research has become more rigorous over the past decade."
Beth Simmons. International Law, in Handbook of International Relations, Sage Publications, 2012, pp.352-378 http://www.ejil.org/pdfs/25/3/2520.pdf