Using an endogenous growth model, this paper examines the growth and welfare effects of the allocation of foreign aid in the recipient economy. As public inputs are a productive factor, a rise in the allocation of aid to the public inputs increases growth and hence the welfare of the economy. However, raising the ratio of aid to pollution abatement may not help an economy, because it crowds out public inputs. Since public inputs are also partly financed by income taxation, the welfare-maximizing income tax rate is larger than the growth-maximizing rate, because a portion of the aid constitutes a lump-sum transfer and can increase household consumption and hence welfare.