This paper aims to draw attention to the social and micropolitical dimensions of attempting to implement improvements within healthcare organisations. It is argued that quality improvement initiatives, like other forms of organisational innovation, will fail unless they are conceived and implemented in such a way as to take into account the pattern of interests, values and power relationships that surround them. Drawing on examples, it is suggested that innovators can intervene more successfully if they understand how the benefits and costs of interventions are likely to be distributed among stakeholders within their setting, how different but equally legitimate value sets may structure peoples' understanding of them and how the nature of the interventions themselves (and, in particular, the shape of their hard core and soft periphery) might provide scope for redesigning or adapting interventions in ways that are likely to make them both more effective and politically feasible.