Work-related self-identities are central to middle leaders' work. Their development takes place in social, policy and personal contexts. At the core of middle leaders' work-related identities lie values that guide how they interact with colleagues, students and senior management staff when trying to shape and implement departmental and school policies. These are revealed in the ways in which they work with colleagues and students to develop collaborative cultures and distributed leadership of a sort. However the negotiations encompass micro-political processes and the asymmetrical distribution of power that normally exists in hierarchical organisations.