Chapter 7 discusses the law applicable to shareholder treaty claims. It argues in favour of an integrated approach to the applicable law, that is, one that gives proper weight not only to the applicable IIA provisions but also to general international law and national law. The reason for this is, first, that IIA provisions, including applicable law clauses, commonly require the application of the three sources of law. Second, overlaps between international and national law claims call for consideration and application of this latter legal system. And third, admissibility determinations are not focussed on the scope of treaty provisions containing consent to international jurisdiction but on the content of specific claims (thus often involving substantive aspects).