In recent years over half of all African states have re-introduced some form of universal basic service provision, though many more have done so in education when compared with health. Most existing explanations of these developments have emphasised the importance of demand side factors associated with democratisation. This paper argues that while democratisation has been important in generating pressure for reform, alliances with actors outside the state – such as donors and non-state service providers – have been the critical enabling factor allowing weak states to overcome their capacity constraints and respond. Two illustrative case studies are used to show how variation in alliance opportunities has led to differences in outcomes both between social sectors and across countries. An inter-sector comparison of health and education policy in Tanzania shows how a difference in donor policy preferences between sectors – donors having converged behind the principle of universal primary education but not universal healthcare – has led to variation in alliance opportunities and hence policy outcomes. A ‘least likely’ case of healthcare reform in Lesotho shows how an alliance with a non-state provider has made difficult reforms possible.