This article synthesizes interview data from evaluation directors and top executives of philanthropic foundations on how evaluation might better advance their missions. In key informant interviews, respondents commented on the purposes of evaluation from the foundation's perspective, challenges to effective evaluation, and the means by which evaluation could be made more valuable to foundations. Informants emphasized promoting accountability, improving programs, advancing organizational learning, and disseminating intervention models as desired uses of evaluation. Application of appropriate research techniques, relevance and timing of evaluation products, and internal thinking and social dynamics within foundations were cited as challenges to evaluation. Emerging concerns include the need to evaluate achievements of foundations as a whole and for evaluation to further develop as a science. In terms of increasing the value of evaluation, the current study indicates the importance of improved relationships and dialogue between evaluators and foundation personnel, stronger leadership consensus within foundations regarding evaluation, and safeguarding of the evaluation process.