This accessible textbook presents an up-to-date and scholarly overview of the law of foreign investment, as well as a comprehensive and succinct analysis of the main principles and the standards of treatment available to foreign investors in international law. The book is authoritative and multi-layered, offering an analysis of the most pressing issues. It is an insightful assessment of recent trends in case law on the interpretation of established and evolving principles, from both developed and developing country perspectives. A major feature of this book is that it deals with the emerging tension between the law of foreign investment and other competing principles of international law. It proposes a number of ways and means of achieving a balance between these principles. It recognizes the need to protect the legitimate rights and expectations of foreign investors on the one hand, as well as the need not to unduly restrict the right of host governments to implement their public policy, which includes the protection of the environment, human rights, and the promotion of social and economic justice within the host country. This is perhaps the first textbook of its type authored by a truly international lawyer with experience of teaching, research, and advisory work in both the developed and developing world over the past twenty years. The wealth of experience that the author brings to the task allows him to develop unique insights into the interplay between the law, economics, and politics of foreign investment, making this book essential reading for students, scholars, practitioners, and diplomats interested in the contemporary law of foreign investment.