Identification and measurement of the social costs of rent-seeking (and associated rentdefending and rent-avoiding) in projects in developing countries have been neglected. This is in spite !1f a voluminous literature on the methodology and practice of project evaluation, an.i intense scrutiny of project activities by agencies responsible for their funding. The potential for social costs from rent-seeking in such projects is explored in this paper, with some illustrative ex,mples from agriculture"'based rural development projects. Other social costs indirectly resulting from rent-seeking activities are also described.