This book is the first comprehensive monography dedicated to general exception clauses in international investment law. The inclusion of these clauses in investment contracts is a reaction to the severe doubts about the legitimacy of international investment law. They seek to strike a more equitable balance between investment protection and non-economic objectives, such as the protection of public health. Based on an empirical study on the prevalence of these clauses in current contract practice, it sheds light on the origins of these clauses in world trade law and offers an explanation for their notable omission in early investment contracts. After discussing the advantages and risks of general exceptions in investment law, it highlights their potential future interpretation by arbitral tribunals. Finally, the study analyses the interplay between general exceptions and selected standards of protection, such as the prohibition of expropriation and the standard of fair and equitable treatment.