Atypical depression, with features of hypersomnia, hyperphagia, anergia, and rejection sensitivity, is a common presentation of major depressive disorder. There are few available effective therapies for this disorder. We test modafinil, a novel wake-promoting agent, as monotherapy for atypical depression in a double-blind, placebo-controlled, relapse prevention trial after open-label treatment. We found that modafinil significantly improved atypical depression symptoms during 12 weeks of open-label treatment.