The usual cause of action in investment disputes has hitherto been the taking of property. Though, as was claimed, customary international law recognised an international minimum standard of treatment of a foreign investor, the violation of this standard outside the context of the taking of property was seldom discussed. The growth of such a customary law was dealt with in Chapter 4 above. It forms a prelude to the discussion here. That chapter dealt with the manner in which the creation of an international standard was effected and the conflicts which attended it. But, investment treaties have sought to iron out such conflicts and provide recognition of certain standards of treatment of investments as between the parties to such treaties. It is only with the spelling out of the different standards of treatment in the investment treaties that the breach of treatment standards has become a distinct head of liability distinct from the taking of property. In more recent disputes, the failure to provide treatment according to standards prescribed in investment treaties has become important, especially in the context of Chapter 11 of the North American Free Trade Agreement (NAFTA). The vigour with which disputes have arisen between the two developed-country participants in NAFTA, largely on the basis of treatment standards and novel theories of the taking of property, has opened up new possibilities in the field.