Contractual practices and the applicable law on the composition of three-member tribunals normally provide for each party to select a co-arbitrator unilaterally. This procedure may make the co-arbitrators appear partial and may lead to improper dissenting opinions and premature resignations, which may ultimately threaten the confidence in arbitration and arbitral awards, but the procedure does not remain common for nothing. The arbitration community therefore needs to reconsider the appointment procedure on a solid and deliberate basis, and such a basis is what the article provides. A number of experienced arbitration practitioners have advocated against the procedure for some of the reasons above, whereas other experienced arbitration practitioners have defended the procedure because of its practical advantages and underlying rationales. Each of the previous contributions to the debate sheds light on some important aspects of the procedure but leaves certain aspects and arguments unconsidered.

The article approaches the appointment procedure from a neutral position. It identifies and considers the relevant rules, practices, and arguments in order to discuss the procedure’s implications and the possible legal and contractual adjustments that may change these implications. The article thus provides a theoretical contribution of practical relevance to the arbitration community.