During a seven-year period, thirty patients with achalasia of the esophagus were treated by pneumatic dilatation without complications. Only twenty patients could be followed with a mean follow of 32 +/- 23 months after their initial dilatation. Excellent to good results were obtained in more than 75 p. cent of the group. Most patients have not required a further dilatation. This study suggest to propose a regular supervision of these patients by clinical examination, esophageal manometry and endoscopy.