An example system is configured to: (i) receive data indicating a command to play back audio content, where the data indicating the command to play back audio content is received via a voice input that is detected by a first zone player, (ii) based on the data indicating the command, determine a playback condition comprising a particular zone player, (iii) identify a user account associated with the first zone player, (iv) based at least on (a) the command and (b) the identified user account, determine audio content for playback, and (v) play back the determined audio content via the particular zone player.