The term “complex arbitration” is used here in the same sense as in Professor Bernard Hanotiau's seminal study, Complex Arbitrations: Multiparty, Multi-contract, Multi-Issue and Class Actions.1 As may be inferred from the title of Professor Hanotiau's book, this chapter will primarily deal with the management of (1) a single arbitration involving numerous parties with different interests (“multiparty arbitrations”) and (2) multiple (but related) arbitrations involving identical or closely connected parties (“multi-contract arbitrations”). But it will also say a few words on class arbitrations in international commercial disputes. Section 13.1 of this chapter will illustrate some of the complications that may arise in multiparty and multi-contract situations respectively. It will discuss ways in which those difficulties may be dealt with in practice. Section 13.2 will consider the potential for class arbitrations in practice, especially in light of the abolition of the common law strictures against the third-party funding of arbitration-related proceedings.