After an award has been rendered, one of the parties may seek to challenge it on the basis that the tribunal failed to address an important question which was raised in the arbitration. The Arbitration Act 1996 (‘AA96’) provides for the setting aside (or remission) of an award if the tribunal failed to deal with an issue that was put to it (s 68(2)(d)). Although there is no equivalent provision in article 34 of the UNCITRAL Model Law (‘Model Law’), there are cases decided in several Model Law jurisdictions which show that the courts of these countries are no less willing than the English courts to set aside (or remit) an award if the tribunal failed to deal with an important issue. In policy terms, such cases – which fall perilously close to the dividing line between the merits, on the one hand, and the arbitral procedure, on the other – raise questions over the extent to which supervisory courts should allow themselves to be drawn into second-guessing the merits of the parties’ dispute. At a more technical level, there are two issues which merit close examination: first, which paragraph of article 34 of the Model Law (if any) provides the legal basis for the court’s power to set aside in cases of arbitral omission; secondly, if article 34 does authorise setting aside in these cases, to what extent does the process of reasoning of the courts of Model Law jurisdictions run in parallel with that of the English courts under the AA96. Ultimately, is it possible to say that, in this area, the AA96 provides a preferable solution to that of the Model Law (or vice versa)?