Cataract is a slowly developing eye disease, the prevalence of which rises with age. Although patients often adapt to the diminished visual acuity accompanying the development of cataracts, their functional health may be impaired by poor vision. An index for visual functioning was derived from the literature. As older people often have additional chronic diseases, vision, visual functioning index and chronic co-morbidity were measured. Functional health was measured with different validated instruments. Eighty cataract patients participated in this study and were visited at home. Results showed statistically significant correlations between vision and co-morbidity on the one hand and visual functioning and functional health on the other. As in most participants vision was only slightly impaired, these results might even be more pronounced in patients with mature cataract. We conclude that indications for cataract surgery might not only be derived from visual acuity, but also from visual functioning and functional health.