Capacity building is now mentioned synonymously with school improvement in much of the literature with an absence of debate on the implications of political, social and economic trends. The paper explores capacity building in one low decile, multicultural, New Zealand primary school. From an interpretivist paradigm, a case study and grounded theory approach are used to explore four aspects: 1. the processes that enhance improvement; 2. the internal and external influences on capacity building; 3. the wider societal factors that influence the development of capacity; and 4. the links between capacity building and improvement that were evident. The paper will suggest that capacity building for school improvement is time and context dependent and is unique to the setting. It occurs in response to individual, collective and systemic needs in ways that sustain equilibrium while moving towards improvement. The paper will further explore key attributes: vision, stakeholders as change agents, school culture and professional development. Practices that are examined include knowledge production and utilisation, division of roles and responsibilities and a switching-on mentality. Both groups of factors will be examined as four important themes in the capacity building and school improvement process: situated activity; connectedness; leadership, governance and management; and outcomes. The paper will conclude that the confluence of these contributing factors enables tensions and needs to be managed while ensuring the equilibrium of people, school and system necessary for moving in the direction of improvement.