In recent times, disputes related to nationalisation of investments that marked the 70s and 80s have been replaced by disputes related to foreign investment regulation and indirect expropriation. Foreign investors increasingly make claims for compensation based on governmental regulations, such as placing restrictions on the legal use of property that do not actually remove the owner’s title to the property but nevertheless substantially affect its value or the owner’s control. There is some concern that concepts such as indirect expropriation may be applicable to regulatory measures aimed at protecting the environment, health and other welfare interests of society. How has state practice defined and articulated the difference between an indirect expropriation requiring compensation and a governmental measure impacting an investment but not requiring compensation? How have arbitral tribunals drawn the line? Has the doctrine shed any additional light on this distinction? This survey provides factual elements of information on jurisprudence, state practice and literature related to “Indirect Expropriation” and the “Right to Regulate”. It presents the issues at stake and describes the basic concepts of the obligation to compensate for indirect expropriation, reviews whether and how legal instruments and other texts articulate the difference between indirect expropriation and the right of the governments to regulate without compensation and attempts to identify a number of criteria emerging from jurisprudence and state practice for determining whether an indirect expropriation has occurred.