You should start off by providing a definition of fragmentation in international law. This would definitely involve discussion of the nature and structure of the international legal system. Your second section should examine practical cases of fragmentation on account of the diversification of legal regimes and the proliferation of international courts and tribunals. You should always analyse these by reference to available case law, such as the Mox Plant case or the divergent views of the ICJ (Nicaragua case, Genocide Convention case between Bosnia-Herzegovina and Serbia) and the ICTY (Tadić case) on the issue of effective versus overall control. Then, you will consider the report of the ILC Study Group; you will criticize the approach taken by the Study Group that the current conflict of norms principles (lex specialis, lex posterior) or the interpretation ‘in accordance with the relevant international law’ (Art 31, para 3c VCLT) suffice to address the threat of fragmentation. It is also worth pondering whether fragmentation is really a problem or something positive and, at the end of the day, inherent in the international legal system (see article by Simma).