As parties to the Montreal Protocol consider an amendment to phase down hydrofluorocarbons (HFCs), one critical concern is whether suitable alternatives for air-conditioning applications are available and adequately demonstrated for cooling capacity and energy efficiency under conditions of high ambient temperatures. Given the critical importance of these applications, one option being considered by parties is to provide a time-limited exemption for those uses in countries that could be adversely impacted by high ambient temperatures. This paper looks at a number of options for how such an exemption might be structured.