In the course of introducing a themed issue of the journal on "Innovation in Teacher Education', we lay out an argument for re-examining the meaning of innovation in the field, shifting it away from the dominance of the economistic and technological. Acknowledging its status as a 'buzzword', we distinguish between purposes for innovation and, in particular, between changes driven by arguments for social mobility and those driven by social justice and equity. Two imperatives for innovation underpinned by arguments for social justice and equity are identified: the concept of a 'teacher education debt', built on Ladson-Billings' more general notion of 'education debt'; and the humanization of learning, teaching and becoming a teacher as person-centred, relational practices. The final section of the article introduces each of the six papers in the context of the discussion in previous sections about these imperatives for change.