Deference may operate akin to an order, such that the second-order reasons for recognising a State’s authority shut off the adjudicator’s own exercise of decision-making authority. This is Raz’s understanding of the impact of recognising another actor’s authority; the recognition of authority creates in effect a duty to follow the authority’s decision. Two modes of deference reflect this understanding of authority. In a ‘deference as submission’ mode, a domestic decision becomes dispositive of the outcome of an international adjudicator’s enquiry on the issue to which deference relates. This mode of deference is introduced in Section A. At the other end of the deference spectrum, a ‘deference as control’ mode also reflects this approach to authority albeit in reverse: the international adjudicator’s authority is treated as dispositive, precluding any reference to second-order reasons for deference to a domestic decision-maker’s authority. This mode of deference is introduced in Section B. Although they sit at opposite ends of the deference spectrum, both modes of deference are considered together in this Chapter because a conclusive approach to authority informs their operation.