This chapter considers what a tribunal does when it hears a case substantively. The first section will describe how the substantive hearing of an international commercial arbitration might normally proceed. The second section will discuss the problem of maintaining a level playing field during the substantive hearing, so that the proceedings do not favour one party over the other. It will comment on the difficulty of differing professional standards among advocates appearing in an international commercial arbitration from different jurisdictions, and how a tribunal might ensure that party representatives appearing in the arbitration are held to the same minimum professional standards. In this respect, reference will be made to the IBA Guidelines on Party Representation. The third section will cover techniques for ensuring that a hearing proceeds in an expeditious, cost-efficient, and fair manner. It will focus in particular on the cross-examination and how to avoid wasting time on pointless cross-examination. This is because much valuable time in a substantive hearing is lost on prolonged, but ineffective, cross-examination. Unless the tribunal acts to curb such practice, the substantive hearing will overrun its allotted time, leading to substantial increases in cost and unwelcome adjournments.