Introduction: Clinical guidelines for the treatment of achalasia encourage surgical myotomy for patients under age 45, based on poor outcome of balloon dilatation of patients in this age group and a perceived higher operative risk in older patients. Despite these guidelines many patients are referred for surgery after a previous balloon dilatation and the comparison of risk from laparoscopic myotomy in the younger and older age groups has not been well documented. The purpose of this study was to evaluate the impact of previous therapy and age on the outcome of laparoscopic myotomy. Methods: Retrospective chart review of patients who had laparoscopic myotomy with partial fundoplication from 1996 to 2005. Data including symptom evaluation, previous medical therapy, operative data and results of esophageal manometry were recorded. In a subgroup of patients, a timed barium swallow was obtained postoperatively. Success was defined as near or complete resolution of dysphagia and regurgitation. Patients younger than and older than 45 years were compared. Results: Myotomy was performed in 106 patients. There were 62 patients in the ≥45 years group [58 (IQR 51-67)] and 44 in the <45 years group [36 (IQR 29-42)]. Duration of symptoms, use of antisecretory medication, and frequency of dysphagia, regurgitation, and heartburn were similar in both groups. 35 patients had previous balloon dilatation, and there was no difference between older and younger patients (35% v 30%, p=0.54) Findings on manometry (sphincter length, resting pressure, sphincter relaxation, esophageal pressurization, vigorous body contractions) were similar in both groups. The frequency of perioperative complications was similar, but the mean length of hospital stay was longer in older patients (2.9 v 2.2 days, p=0.005). Relief of regurgitation and dysphagia were similar in both groups (TABLE). The rate of development of heartburn was also similar. A timed barium swallow was performed in 40 patients and there was no difference in emptying between groups. A previous balloon dilatation did not affect outcome of myotomy. Overall phycisian assessment of success was similar in both groups (98% v 91%) and more than half were asymptomatic at followup. Conclusion: Laparoscopic myotomy with partial fundoplication is an effective therapy for achalasia in all patients regardless of age and outcome is not affected by previous pneumatic balloon dilatation.