The question of costs has a lower profile than some parts of the arbitral process, but is of no less importance to parties. Klaus Reichert, barrister in Dublin and at Littleton Chambers in London, and James Hope, solicitor-advocate at Skadden Arps Slate Meagher & Flom LLP, review the treatment of costs in key rules and laws, and then discuss ways in which costs can be used to police the parties’ conduct. They conclude by proposing a model procedure for dealing with costs