Odynophagia and dysphagia are common symptoms of treatable disorders of the esophagus in patients with AIDS. Esophageal candidiasis is the most frequent cause of these symptoms. In patients with AIDS or AIDS-related complex, thrush in combination with odynophagia or dysphagia almost certainly indicates the presence of esophageal candidiasis. Other causes of swallowing disorders in AIDS include opportunistic infection of the esophagus with herpes simplex virus, cytomegalovirus, or, rarely, cryptosporidiosis. Recently, ulcerative esophagitis in AIDS associated with unidentified viral-like particles has been described. Infrequently, Kaposi's sarcoma or lymphoma may involve the posterior pharynx or esophagus, respectively. Because Candida esophagitis is so frequently the cause of odynophagia and/or dysphagia in AIDS, it is suggested that in most cases, a therapeutic trial with an antifungal agent, like ketoconazole, may be appropriate before radiologic or endoscopic examination. Further investigation can be reserved for patients who do not respond to this trial or who have clinical evidence suggesting another esophageal disorder. Herpes simplex and cytomegalovirus esophagitis can be treated with antiviral agents, such as acyclovir and ganciclovir, respectively. Maintenance therapy with antifungal agents to prevent recurrent esophageal candidiasis may be beneficial, but the efficacy and cost effectiveness of this approach remain to be determined. Because of the increasing numbers of patients with AIDS, frequency of esophageal disorders, such as candidiasis, in these patients and the morbidity of these disorders, an expansion of clinical research efforts to determine effective treatment and prophylaxis for these disorders is warranted.