The concept of student voice is problematic. This paper considers two different traditions which theorise the notion of voice. The first is located within critical sociological studies of youth identity, drawing upon the notion of the often silenced voices of the marginalised, "Othered" or subordinated as a means of exposing oppressive power relations. The paper outlines an alternative theorisation of student voice we call, following Bernstein, the "sociology of pedagogic voice". Bernstein's distinction between voice and message plays a key role here in discriminating between: social and pedagogic identities; specialised voices based upon power relations and the realisation of those relations revealed in "talk"; and dominant and subordinate voices and the "yet to voiced". This conceptualisation of voice suggests that pedagogies construct the voice/message which teachers and researchers hear--whether "classroom talk", "subject talk", "identity talk" or "code talk". Caution is needed in assuming that power relations can be changed through the elicitation of student talk.