Objective: To study the prevalence and distribution of visual impairment and eye diseases by age and gender in an urban institutionalized population. Design: Cross-sectional study. Participants: Four hundred three residents of nursing homes and hostels. Methods: Fourteen nursing homes were randomly selected from 104 nursing homes and hostels located within a 5-km radius of each of nine clusters studied in the Visual Impairment Project (VIP) urban cohort. Participants completed a standardized orthoptic and dilated ophthalmic examination, including measurement of visual acuity and visual fields. The major cause of vision loss was identified for participants with visual impairment. Main Outcome Measures: Presenting visual acuity and ophthalmic diagnoses. Results: The participants' mean age was 82 years (standard deviation, 9.24), with an age range of 46 years to 101 years. Women outnumbered men by 318 to 85. Seventy-one (22%) of 318 women had bilateral profound visual impairment (blindness), defined as best-corrected visual acuity <3/60 and/or visual field constriction <5°compared with 10 (12%) of 85 men. However, this difference is not significant when age-standardized. Age-related macular degeneration was the principal diagnosis of vision loss in the better eye of 74 (44%) of the 167 participants with bilateral low vision (<6/18 and/or visual field constriction to <20°radius). The age-adjusted rate of blindness or profound visual impairment in the VIP institutional cohort of 5.2% (95% confidence interval [Cl], 1.8, 8.6) was significantly greater than in the VIP urban and rural cohorts of 0.13% (95% Cl, 0, 0.25) and 0.29% (95% Cl, 0, 0.57), respectively. Conclusions: Underestimation of visual impairment may occur in residential population-based studies that exclude institutional or residential nursing homes and hostels for the aged citizens. Expanded methods are required for visual assessment in institutional populations. (C) 2000 by the American Academy of Ophthalmology.