Several lessons have been learned within the sector.
We know, for example, that sustainable service delivery depends on decentralized authority, on public- and private-sector resources and expertise, with adequate central support, and on communities empowered to make well-informed choices about technical, management and financial options.
We know that going to scale requires central support through an enabling policy environment, adequate funding and sufficient human-resource capacity.
Priority attention and specific techniques are needed to reach the poor and address gender inequities, and high-quality, disaggregated information and strategic partnerships are needed to effectively leverage funds and target activities.
We know, too, that interventions will have more impact if approaches are intersectoral. In emergencies, preparedness and coordination are key to an effective response.