The registration of resting pressures and motility activity has considerably increased our knowledge of the normal functioning of the esophagus. We have not jet solved all the methodological problems of manometry; however perfusion manometry, which is used today, has enabled us to make an exact cassification of functional disorders and adequate therapy. An understanding of the methodological problems involved is necessary for the correct use of the manometric method and the correct interpretation of its results. This precondition has not always been observed, especially in discussion of the gastro-esophageal closure mechanism, and has thu given rie to much confusion. An attempt at a critical evaluation should be the basis for future discussion.