Aim: The research aimed to explore the extent to which assistant headteachers were contributing to the leadership of primary schools. Nationally, leadership groups were introduced in September 2000 and a new post of assistant headteacher was created. The research identified the rationale for the appointment, examined the variety of leadership activity that assistant headteachers were involved in and sought to determine the impact that this had in their schools. The enquiry focused on actions that were agreed by the participants to be leadership in nature, as opposed to managerial activity.