There is a healthy debate about how to achieve poverty reduction in developing countries, but not enough discussion of what we mean by “poverty reduction.” “Poverty reduction” is often used as a short-hand for promoting economic growth that will permanently lift as many people as possible over a poverty line. But there are many different objectives that are consistent with “poverty reduction,” and we have to make choices between them. There are trade-offs between tackling current and future poverty, between helping as many poor people as possible and focusing on those in chronic poverty, and between measures that tackle the causes of poverty and those which deal with the symptoms. Because donors focus on just one dimension of poverty reduction (growth) they marginalise other legitimate objectives such as reducing chronic poverty or providing social services in countries that cannot otherwise afford them. Because donor agencies do not recognize these different objectives explicitly, there are important negative consequences for the choice and management of individual aid programmes, and for donors’ ability to make transparent and evidence-based decisions about the composition of their portfolio. Aid could be more effective if there were greater recognition of the different dimensions of poverty reduction and if this was recognized in the objectives for and incentives in aid agencies. There is an ethical case for a global system of social justice that provides long-term, redistributional transfers of resources to the world’s poor, to enable them to lead better lives while their country is developing, even if there is no expectation that these transfers will accelerate economic development. Reasonable people can disagree about whether this is desirable but the existing hegemonic definition of poverty reduction does not sufficiently acknowledge this as a legitimate goal or permit a meaningful discourse about how it might be achieved.