The term 'governance' is popular but imprecise. It has at least six uses, referring to: the minimal state; corporate governance; the new public management; 'good governance'; socio-cybernetic systems; and self-organizing networks. I stipulate that governance refers to 'self-organizing, interorganizational networks' and argue these networks complement markets and hierarchies as governing structures for authoritatively allocating resources and exercising control and co-ordination. I defend this definition, arguing that it throws new light on recent changes in British government, most notably: hollowing out the state, the new public management, and intergovernmental manage-ment. I conclude that networks are now a pervasive feature of service delivery in Britain; that such networks are characterized by trust and mutual adjustment and undermine management reforms rooted in competition: and that they are a challenge to governability because they become autonomous and resist central guidance.