PURPOSE:: To evaluate the effectiveness of tacrolimus in patients with noninfectious intermediate, posterior, or panuveitis needing a two-immunosuppressive-agent regimen. METHODS:: Design: Retrospective cohort study. Setting: Two tertiary-care uveitis practices at academic medical centers. Patient population: Thirty-two patients with noninfectious intermediate, posterior, or panuveitides in whom single-agent immunosuppression was inadequate to effect successful corticosteroid sparing. Intervention: tacrolimus, added as the second immunosuppressive agent. Main outcome measure: successful corticosteroid sparing, defined as inactive uveitis at a dose of prednisone ≤7.5 mg/day. RESULTS:: Active uveitis was present in 65.6% of patients at initiation of tacrolimus, and the median time to inactive uveitis was 1.5 months (95% confidence interval 1.2, 4.08). The median time to successful corticosteroid sparing was 3.9 months (95% confidence interval 1.41, 6.67), and by 6 months of follow-up successful corticosteroid sparing was achieved in 75% of patients. Tacrolimus was discontinued for side effects in five patients, three for tremor, and two for hyperglycemia. All side effects were reversible with tacrolimus discontinuation. CONCLUSION:: Tacrolimus seems to have efficacy as a second immunosuppressive agent in two-immunosuppressive drug regimens, when a single agent does not permit successful corticosteroid sparing. Side effects were reversible with tacrolimus discontinuation.