In this article, we shed light on the debate about the financial performance of socially responsible investment (SRI) mutual funds by separately analyzing the contributions of before-fee performance and fees to SRI funds’ performance, and by investigating the role played by fund management companies in the determination of those variables. We apply the matching estimator methodology to obtain our results and find that in the period 1997–2005, US SRI funds had better before- and after-fee performance than conventional funds with similar characteristics. The differences, however, are driven exclusively by SRI funds run by management companies specialized in SRI. While these funds significantly outperform similar conventional funds, funds run ...