This article discusses the impact of a leadership development programme that attempted to develop leaders and leadership amongst actual and prospective managers within a large local authority social work service. It concentrates on empirical findings that illustrate the forms of change that took place at the level of the individual and those that extended beyond leader development and into leadership behaviours that involved collective and collaborative action. It sets the discussion in the context of previous studies into leadership development activities before briefly discussing the methods of evaluating training and education activities. The evaluation aimed to assess the impact the programme had on individual leadership practice, the participants’ teams and on the provision of services through attempting to evidence observable performance outcomes. The findings suggest that there were elements of the programme that had sustainable impact at the level of the individual and in wider operational terms within the service.