To examine the long-term efficacy and safety of the intravitreal 0.2-μg/day fluocinolone acetonide implant (FAi) to treat noninfectious uveitis (NIU) of the posterior segment (PS). Three-year, phase III, multicenter, randomized, double-masked, controlled, prospective study (clinicaltrials.gov, NCT02746991). Overall, 153 patients in India with NIU-PS in ≥ 1 eye (with or without anterior uveitis) for ≥ 1 year who had ≥ 2 separate recurrences of uveitis requiring ocular injections or systemic therapy in the prior 12 months. Patients were randomized 2:1 for baseline FAi or sham injection and monitored for main outcome measures. Incidence and timing of uveitis recurrence, use of adjunctive therapy, best-corrected visual acuity, central foveal thickness, and monitoring of intraocular pressure (IOP)- and cataract-related events over 36 months. Overall, 153 patients (FAi, n = 101; treated sham, n = 52) were enrolled. Fluocinolone acetonide implant-treated eyes had significantly reduced uveitis recurrence rates versus treated sham (46.5% vs. 75.0%, respectively; P= 0.001) and a longer median time to recurrence (1116.0 [95% confidence interval, 847.00 to not evaluable] vs. 190.5 [95% confidence interval, 100.0-395.0] days for treated sham). Systemic adjunctive treatments were similar between groups, but fewer FAi-treated eyes required adjunctive injections (8.9% vs. 51.9% for treated sham). Visual outcomes were similar between groups, and residual macular edema was more common at 36 months in treated sham versus FAi-treated eyes (46.2% vs. 24.2%, respectively). The FAi-treated group had a lower central foveal thickness from month 12 onward. Intraocular pressure-lowering surgeries were stable in both groups, but, as expected, rates of IOP elevations were more frequent in the FAi-treated group than in the treated sham (IOP > 25 mmHg: 23.8% vs. 3.8%; IOP > 30 mmHg: 16.8% vs. 1.9%, respectively), and FAi-treated eyes had a higher incidence of cataract surgery than the treated sham (70.5% vs. 26.5%, respectively). In patients with NIU-PS, the 0.2-μg/day FAi is associated with reduced-uveitis recurrence and increased time to first recurrence while controlling macular edema, maintaining stable IOP levels, and providing an expected safety profile, including a higher occurrence of cataract formation over 36 months. The authors have no proprietary or commercial interest in any materials discussed in this article.