Mönestam E - In this prospective, population-based cohort study, the researcher reported the longitudinal visual functional outcome after cataract surgery over 20-years. In 1997-98, 114 patients (mean age was 60.6 years) undergoing cataract surgery responded preoperatively to the same visual function questionnaire, 2-4 months postoperatively, 5, 10, 15 and 20 years postoperatively. Most patients also had the best-corrected visual acuity routine ocular examination. This prospective, 20-year follow-up study gives estimates of longitudinal visual outcomes. For the majority, particularly younger patients also after 20 years, cataract surgery offers excellent long-term visual rehabilitation, with a low need for YAG-laser capsulotomy. The findings of this research are valuable for counseling younger cataract and refractive patients with clear lens surgery.