A retrospective analysis of 115 consecutive patients who underwent endoscopic sinus surgery for chronic sinusitis was conducted to evaluate the effect on outcome of variables including previous sinus surgery, allergy, asthma, and computed tomography stage of disease. Outcome was assessed in each patient by a survey in which the patient rated the benefit of surgery in terms of percent improvement in different symptoms compared with symptoms before surgery. Outcome was also assessed by the need for revision surgery and the presence of endoscopic criteria for failure. The results indicate that allergy and previous sinus surgery are associated with lower individual symptom scores, but no variable was associated with overall symptomatic failure. Previous sinus surgery was strongly associated with the need for subsequent revision surgery. The computed tomography stage was strongly associated with endoscopic evidence of failure. In conclusion, both history of previous sinus surgery and computed tomography stage of disease are correlated to poor outcomes after endoscopic sinus surgery.