Glaucoma is one of the most frequent causes of blindness in the world. Although there are several different subforms of glaucoma, their final common pathway is an atrophy of the optic disc leading to progressive visual field defects and finally total blindness. The loss of function in glaucoma is irreversible, i.e. early detection of the disease is the most important part of its therapy. Early detection, however, requires improved knowledge about the disease in the general population and the active help of all general practitioners, explaining their patients the insidious nature of the disease.