Glaucoma is associated with changes of the optic disc topography. Using color stereo photographs we examined non-quantitative signs in 584 optic discs of 308 patients with chronic primary open-angle glaucoma and in 383 optic discs of 236 age and refraction matched normal subjects. Only one eye per patient and normal subject was chosen for statistical analysis. Highest predictive value to differentiate between normal and glaucoma eyes had the parameters 'changes in the juxtapapillary retinal nerve fiber layers' (86.7%), 'abnormal size (79.8%) and abnormal location (68.6%) of the parapapillary chorio-retinal atrophy', 'smallest neuroretinal rim part outside of the temporal horizontal disc sector' (78.5%), and area with cupping larger than area with pallor' (68.2%). Characteristics with high specificity and low sensitivity were 'optic disc haemorrhages', 'bared cilioretinal arteries', and 'bared circumlinear vessels'. With their evaluation being independent of sophisticated techniques the non-quantitative parameters are helpful for the ad hoc diagnosis of glaucomatous optic nerve damage.