Interpretation in Good Faith and Its Relevance in International Investment Law

The principle of good faith drives forward the interpretation of provisions of international investment treaties. While the tribunal must interpret the treaty in good faith, the parties – as well as the tribunal – are also obliged to fulfil their treaty and contractual obligations in good faith. This creates a complex interplay of interpreting customary international law in the form of behavioural obligations. During this period of reconsideration of the system, these interpretative and behavioural aspects of the principle of good faith may provide an opening to a more cohesive system of investment protection. The following contribution approaches the tribunals’ power to interpret the good faith behavioural obligations of parties and considers its future value.