Introduction: Laparoscopic esophagomyotomy is the preferred approach to patients with achalasia of the esophagus, However, there are very few long-term follow-up studies (> 10 years) in these patients. Objective: To perform a very late subjective and objective follow-up in a group of 67 patients submitted to esophagomyotomy plus a partial antireflux surgery (Dor's technique). Material and Methods: In a prospective study that lasted 30 years, 67 patients submitted to surgery were divided into 3 groups: group I followed for 80 to 119 months (15 patients); group 11, with follow-up of 120 to 239 months (35 patients); and group 111, with follow-up more than 240 months (17 patients). They were submitted to clinical questionnaire, endoscopic evaluation, histologic analysis, radiologic studies, manometric determinations, and 24-hour pH studies late after surgery. Results: Three patients developed a squamous cell esophageal carcinoma 5, 7, and 15 years after surgery. At the late follow-up, Visick III and IV were seen in 7%, 23%, and 35%, according to the length of follow-up of each group. Endoscopic examination revealed a progressive nonsignificant deterioration of esophageal mucosa, histologic analysis distal to squamous-columnar junction showed a significant decrease of fundic mucosa in patients of group 111, with increase of intestinal metaplasia, although not significant time. Lower esophageal sphincter showed a significant decrease of resting pressure I year after surgery, which remained similar at the late control. There was no return to peristaltic activity. Acid reflux measured by 24-hour pH studies revealed a progressive increase, and the follow-up was longer. Nine patients developed Barrett esophagus: 6 of them a short-segment and 3 a long-segment Barrett esophagus. Final clinical results in all 67 patients demonstrated excellent or good results in 73% of the cases, development of epidermoid carcinoma in 4.5%, and failures in 22.4% of the patients, mainly due to reflux esophagitis. Incomplete myotomy was seen in only I case. Conclusion: In patients with achalasia submitted to esophagomyotomy and Dor's antireflux procedure, there is a progressive clinical deterioration of initially good results if a very long follow-up is performed (23 years after surgery), mainly due to an increase in pathologic, acid reflux disease and the development of short- or long-segment Barrett esophagus.