Difficult-to-manage mucosal candidal infection has been a hallmark of individuals with advanced infection due to human immunodeficiency virus type 1. In this AIDS Commentary, Drs. Fichtenbaum and Powderly comprehensively review the literature and their experience with refractory candidiasis in such patients. Of interest is their delineation of resistance, a lack of susceptibility to an antifungal agent in vitro among patients with refractory or clinically unresponsive disease. These authors believe that the establishment of resistance should be based upon standards established by the National Committee on Clinical Laboratory Standards, which they propose to define as a failure to respond to systematic therapy with specific doses of itraconazole, fluconazole, or parenterally or orally administered amphotericin B within 14 days. There have been many definitions of "refractory candidiasis," and the one proposed by these authors will be debated; however, this definition has the advantage of establishing a standard by which to judge the efficacy of their proposed algorithm for the treatment of persistent or refractory oropharyngeal candidal infections. Drs. Fichtenbaum and Powderly have performed a useful service in their attempt to bring coherence to the management of this common and often vexing problem.