Recent studies have suggested that diffuse field loss and localized visual field loss in glaucomatous patients may have different pathophysiologic mechanisms. Testing that hypothesis requires that some patients present with purely localized field loss and other patients with purely diffuse loss. This article describes four highly selected patients with elevated intraocular pressures, bilateral damage to the optic nerve head, one eye with a classic glaucomatous visual field defect and in the other eye, in the absence of opacities in the media, a diffuse loss of the visual field. Although purely localized loss is very common, the report illustrates purely diffuse loss in the absence of other causes.