This chapter focusses on a narrow topic: the law applicable to post-award issues. It deals in turn with the law applicable to recognition and enforcement proceedings, to annulment proceedings, and to post-award issues in investment arbitration. Enforcement of arbitral awards typically takes place within the framework of the 1958 New York Convention, but this chapter will also refer to relevant provisions of the UNCITRAL Model Law on Commercial Arbitration, the 1961 Geneva Convention and the ICSID Convention. Issues covered include the law applicable to the following issues: the validity of the arbitration agreement, arbitrability, arbitral procedure, competence of the tribunal, scope of the dispute, public policy, finality of the award and annulment. Particular attention will be given to the extent to which potentially diverse answers arising from the designation of national law may be mitigated by evolving transnational norms for some of the issues examined.