This chapter discusses the role of domestic foreign investment screening legislation and its link to investment treaties. The chapter proceeds to examine the treaty definitions of the concepts of investment and investor and associated controversies. It concludes with an explanation of performance requirements which may be imposed on foreign investors.

The architects of the post-war international economic order set out for the legal framework for liberal international trade underpinned by the GATT regime. Nonetheless, the East–West division necessitated a regime regulating trade between these two camps with the main objective to prevent strategic and technological articles transferred to the Soviet Bloc. Russia joins the Wassenaar Arrangement (the successor of COCOM) while China is still out. The market economy oriented GATT/WTO widens its membership and importantly accepted China in 2001 and Russia in 2012. Its diversified memberships make it a real ‘world trade organisation’ but at the same time introduce huge challenges for its governance, as manifested in the proliferation of national security exception. Whether the national security exceptions is ‘self-judging’ has been debated since the GATT era, but intensified in the past decade owing to the transformation of ‘negative consensus’ to ‘positive consensus’. The ‘self-judging’ debates of national security points to the underlying tension between sovereign as masters of treaties and adjudicator as treaty-interpreters.