We conducted a prospective study of 56 patients aged 70 to 79 years undergoing cataract surgery, in order to determine the impact of surgery on subjective and objective measurements of visual ability. In 46 cases we could obtain all necessary data. Binocular visual acuity, near vision and contrast sensitivity improved due to surgery. Self-assessed ability to perform visually related tasks was examined in form of a questionnaire. The results show that there was no simple relationship between objective measurements and perceived visual ability. An impairment in preoperative visual acuity cannot be related to a specific loss of visual ability. In order to increase the quality of cataract surgery more subtly, subjective aspects of vision must be taken into consideration when operation is decided upon and in the evaluation of the results.