Family histories were taken from 124 index patients, who had presented with either angle-closure or open angle glaucoma to the University Department of Ophthalmology, Manchester, between 1967 and 1972. Their first-degree relatives numbered 886, i.e. siblings, offspring and parents. Relatives were contacted by post and asked to attend for eye examination. Out of a total of 886 relatives, only 187 relatives were actually examined. The reasons for this low attendance rate are discussed; e.g. 423 relatives had already died.