Thirty-three patients treated at the Karolinska Hospital for achalasia of the esophagus during the period 1968--78 have been reexamined. Twenty-eight of these patients underwent pneumatic dilatation. Excellent and good results were obtained in 79% of cases; in 21% the result was considered poor. In 2 cases the esophagus was perforated during dilatation--a perforation rate of 5% of the total number of dilatations. In 6 cases the lower sphincteric pressure was calculated before and after dilatation. It was found to be higher than normal, preoperatively, but reduced to a near-normal value postoperatively.