An initial series of patients with lattice degeneration was reported to the Academy in 1964 and a follow-up report given in 1973. A continuing prospective study of 276 consecutive untreated patients (423 eyes) is now reported with follow-up from 1 to 25 years (average, 10.8 years). Clinical retinal detachments (RDs) occurred in 3 (1.08%) of 276 patients and 0.7% of eyes. Tractional retinal tears were seen in eight (2.9%) patients and 1.9% of eyes; one of these led to a clinical RD. Clinical or progressive subclinical RD occurred in 3 (2%) of eyes with atrophic holes. Subclinical RD was seen in 10 (6.7%) of 150 eyes with atrophic holes, involving 9 (7.5%) of 120 patients, and had a much less serious prognosis than clinical detachment. Prophylactic treatment of lattice with or without holes in phakic, nonfellow eyes should be discontinued.