Since allergic fungal sinusitis was initially described by Millar et al, in 1981, many have tried to define and explain the disorder. It has been labeled as the sinonasal equivalent of allergic bronchopulmonary aspergillosis; however, allergic fungal sinusitis cannot be categorized so easily. According to current literature, there are five major criteria and six associated characteristics, or minor criteria, of patients with allergic fungal sinusitis. This disease is not only difficult to diagnose, but one of the most complicated conditions rhinologists must manage. Endoscopic sinus surgery must be used in conjunction with long-term medical therapy, i.e., oral and nasal corticosteroids, allergen immunotherapy and antifungal therapy to effectively control the problem.