Contractions of collagenous membranes in the posterior cortical vitreous may produce macular pucker and loss of central vision. It is possible to separate these membranes from the retina, and if one succeeds in doing so there is reasonable improvement in central visison. Between December 1976 and September 1978, six patients with macular pucker were operated upon. The clinical details and results are described. The technique used was that of Machemer with the modifications demanded by use of the Klöti vitreous stipper. Several different instruments were used for dissection, the most useful being the joint knife used in stapedectomy.