August Reinisch gives a broad overview of the entire field of international investment law that has emerged as an important subfield of international economic law over the last decades. As a result of the boom of investment arbitration since the late 1990s, core questions of the substantive treatment of foreign investors are analysed. Combining an academic and a practical perspective, this book has been written to provide an introduction to investment law for lawyers, political scientists, economists as well as those interested in international relations.