Abstract
This paper econometrically examines the impact of aid on the well-being of population sub-groups within 48 developing countries. This is a radical departure from previous empirical research of aid effectiveness at the country level, which has looked mainly at the relationship between aid and national aggregates, per capita GDP growth in particular. A specific concern of the paper is the impact of aid on the wealth, education and health of the poorest. Results indicate that while aid improves the well-being of the poorest groups, it is the richer groups that benefit the most.