Imagine, for a second, a school where teachers see themselves as leaders and work together to ensure that all children have access to engaging, high quality instruction every day. How might these teachers define teacher leadership and articulate its purpose? What suggestions would they offer about how teacher leadership can be grown and supported? What might these teacher leaders say about their reasons for choosing to participate in leadership work? The actions and reflections of the 4th-grade teacher team from McWhirter Elementary Professional Development Laboratory School in Webster, Texas, offer an inside look at the self-organizing system of team-based teacher leadership that stands ready to help transform schools.