A method for controlling one or more scent delivery units includes maintaining one or more scheduled events, maintaining one or more scheduled anti-events, and generating, based on the one or more scheduled events and the one or more scheduled anti-events, command data to be communicated to the one or more scent delivery units to control their activation and deactivation. Generating the command data includes identifying a conflicting period of time during which control specified by the one or more scheduled events differs from control specified by the one or more scheduled anti-events and also includes generating command data that gives priority to control specified by the one or more scheduled anti-events. Control for the one or more scent delivery units during the conflicting period of time is in accordance with control logic of the one or more scheduled anti-events and not the one or more scheduled events.