Systems and methods are provided in which a speaker profile-data inquiry is transmitted to a mobile device associated with a first speaker. In response to the speaker-profile-data inquiry, speaker profile data associated with the first speaker is received. Audio data representing a voice input is received. The first speaker is identified as providing the voice input, the identification being based on a comparison of characteristics of the received audio data with the speaker profile data of a plurality of speakers for whom speaker profile data is stored. An instruction, which includes a speaker-relative signifier, is determined from the received audio data, and determining the instruction includes determining a referent of the speaker-relative signifier based on the first speaker profile data. An action indicated by the instruction is performed.