Akademik Veri Yönetim Sistemi
PUBLIC AND PRIVATE INTERNATIONAL LAW BULLETIN, cilt.45, sa.1, ss.38-63, 2025 (ESCI)
The consequences of the fragmentation of international law are clearly observable in the domain of international investment law, which is both influenced by and contributes to this fragmentation. The interaction between investment law and other branches of international law, such as human rights and environmental law, has become increasingly essential. This article examines the necessity of integrating and harmonising investment law with other fields of international law with which it interacts most, including human rights, environmental law, and sustainable development. It proposes the effective application of interpretative methods for treaties as a solution to these issues. When provisions are absent in treaties or when there is a need for harmonised interpretation of existing provisions, the interpretation of international treaties plays a significant role in aligning investment law with other areas of international law. Therefore, as potential solutions, this analysis evaluates the principles of systemic harmonisation outlined in Article 31(3)(c) of the Vienna Convention on the Law of Treaties, the evolutionary interpretation that considers changing circumstances, and the effective interpretation in good faith that takes into account the object and purpose of treaties. These interpretative methods are proposed as fundamental tools for addressing fragmentation and aligning the investor-state dispute resolution process with the broader norms of international law.