Teacher leadership has become an area of significant interest in research and policy terms in recent years. However, as a form of leadership it remains orthodox and conservative, rooted in largely traditional managerialist hierarchies, and disconnected from a critique of the wider policy imperatives that shape the contexts in which leadership is constructed. This article reports on an evaluation study of the work of Union Learning Representatives in a major teaching union in England and suggests that their role offers a new and more fruitful way of considering teacher leadership. Such leadership needs to be genuinely democratic and focused on cohering a professional voice amongst teachers. It is not a leadership concerned with providing ‘vision’, but one rooted in a dialogic and critical process, from which genuinely transformatory possibilities emerge.