In a retrospective study of 114 patients under treatment for chronic glaucoma (81 without and 33 with visual field defect) over an 11-year period of observation, a highly significant correlation between intraocular pressure and progression of visual field defects could be demonstrated. This correlation could be shown for the visual field outer boundary in 81 eyes with ocular hypertension and for typical visual field defects in 33 eyes with chronic glaucoma. The relationship was, however, only significant when both the standard deviation of the annual intraocular pressure and the influence of cataract development upon visual acuity were considered. Quantitative analysis of the results of Goldmann perimetry was by planimetry and took into account only changes during the 11-year observation period.