Background: The paper presents a case-study of how an English principal enacts ‘social justice leadership’ in a secondary school with students recognized as low-income, and/or cultural, racially and linguistically diverse. The educational landscape in England is framed by rapid educational reforms of the educational market including the introduction of academies, free schools, private contracts between schools and the Secretary of State for Education, and accountability for the public purse to Parliament and the public. The result is an educational environment in which market pressures, and their tendencies to inequality, exert a powerful influence within the school system. Expected outcomes: The findings generate new understandings of what social justice means to the leader, including the role and purpose of education, what the leader values about education and the school, and how causes of social injustice are described and understood. Further, the findings reveal types of commitment to tackling social injustice, how these commitments are realized, the potential role of organizational culture, and how situations are mediated when values and policies conflict.