The primary aim of this study was to identify factors that influence outcome of the surgical treatment of achalasia. A secondary aim was to compare outcomes after laparoscopic Heller myotomy and partial fundoplication using either a Dor or Toupet hemifundoplication. Between 1994 and 2002, a total of 78 patients underwent laparoscopic Heller myotomy and partial fundoplication. Preoperative investigations included esophageal manometry, a videoesophogram, and upper gastrointestinal endoscopy with biopsy. In 64 patients (35 males and 29 females), telephone contact was possible at a median 24 months (IQR 14-34). A Dor fundoplication was performed in 41 patients and a Toupet fundoplication in 23. Symptoms were assessed prior to surgery and at follow-up by an independent physician using standardized definitions to grade the severity of dysphagia, regurgitation, and chest pain. To assess outcome, dysphagia was categorized as persistent or resolved. Persistent was defined as dysphagia that occurred on a weekly or daily basis. Resolved was defined as dysphagia that occurred occasionally or not at all. At follow-up, patients were asked to make a personal evaluation of their outcome as to whether (1) their swallowing was improved by the procedure, (2) they were satisfied with the outcome, and (3) they would undergo surgery again under the same circumstances. There was a significant improvement in dysphagia and regurgitation scores after surgery (P<0.05). The scores for chest pain/heartburn remained unchanged. By physician assessment, dysphagia was resolved in 49 patients (77%) and persisted in 15 (33%). By patient assessment, 62 patients (97%) reported an improvement in the symptom of dysphagia, and 60 (94%) stated that they were satisfied with their improvement and would undergo surgery if they had to make the choice again. On univariate analysis, patients who had resolution of their dysphagia had a significantly higher resting lower esophageal sphincter (LES) pressure prior to myotomy (P=0.01) and on multivariate analysis only a high resting LES pressure prior to surgery was a predictor of resolution of dysphagia (P=0.015). Outcome comparison of patients with Dor and Toupet fundoplications showed no significant differences in physician assessment of postoperative symptom scores and resolution of dysphagia, patient assessment of outcome, or postoperative use of proton pump inhibitors. Ninety-four percent of patients are satisfied with their surgical myotomy for achalasia. By physician assessment dysphagia was resolved in 77% of patients. A high LES resting pressure before surgery predicted resolution of dysphagia.