A method for a computing device, the method comprising: receiving a first message comprising (i) an identification of a microphone device associated with a media playback system and (ii) a voice command comprising a media playback command received by the microphone device, wherein the media playback system comprises one or more zones each comprising one or more playback devices; selecting an audio response zone from the one or more zones to play an audio response to the voice command based on the identification of the microphone device and information in a database comprising one or more data items indicating an assignment of the identification of a microphone device to a particular zone of the media playback system; and causing at least one playback device of the one or more playback devices of the audio response zone to play the audio response; wherein: causing at least one playback device of the audio response zone to play the audio response comprises transmitting to the audio response zone, a second message indicating the media playback command and causing the audio response zone to play back media according to the media playback command; the database further indicates that the microphone device is associated with first and second zones of the media playback system; and the first zone is selected as the audio response zone when at least one of: the first zone is associated with media content, and the second zone is not associated with media content. receiving a first message comprising (i) an identification of a microphone device associated with a media playback system and (ii) a voice command comprising a media playback command received by the microphone device, wherein the media playback system comprises one or more zones each comprising one or more playback devices; selecting an audio response zone from the one or more zones to play an audio response to the voice command based on the identification of the microphone device and information in a database comprising one or more data items indicating an assignment of the identification of a microphone device to a particular zone of the media playback system; and causing at least one playback device of the one or more playback devices of the audio response zone to play the audio response; wherein: causing at least one playback device of the audio response zone to play the audio response comprises transmitting to the audio response zone, a second message indicating the media playback command and causing the audio response zone to play back media according to the media playback command; the database further indicates that the microphone device is associated with first and second zones of the media playback system; and the first zone is selected as the audio response zone when at least one of: the first zone is associated with media content, and the second zone is not associated with media content. causing at least one playback device of the audio response zone to play the audio response comprises transmitting to the audio response zone, a second message indicating the media playback command and causing the audio response zone to play back media according to the media playback command; the database further indicates that the microphone device is associated with first and second zones of the media playback system; and the first zone is selected as the audio response zone when at least one of: the first zone is associated with media content, and the second zone is not associated with media content. the first zone is associated with media content, and the second zone is not associated with media content.