Do women benefit from participating in women-only, “enclave” groups? Specifically, do such groups benefit their individual members? This question underlies a number of influential normative theories of inequality but remains underexplored despite the ubiquity of these groups in the organizational life of legislative, party, civic, education, and interest-group settings. This article develops multiple objective and subjective dimensions of individual empowerment that such groups may produce, specifies the institutional conditions that facilitate these benefits, and conducts a comparison with men’s groups. To address selection effects, we use a controlled experiment randomizing gender composition and other group characteristics. We find that female enclaves benefit their members, but only under unanimous rule and for most, but not all, forms of empowerment. Men-only groups do not help men, suggesting that enclaves work because they empower the powerless.