Tubulointerstitial nephritis and uveitis syndrome (TINU) is a specific form of uveitis that is unfamiliar to most ophthalmologists. Thus, it is frequently overlooked in differential diagnosis. We hypothesized that recognition of subsets of uveitis can facilitate the diagnosis of rare entities such as TINU. Retrospective case series. One thousand nine hundred eighty-five patients with uveitis. We performed a computerized database analysis of patients evaluated for uveitis at the Casey Eye Institute from September 1985 until May 2005. The database includes details about ocular inflammation, including specific diagnosis, anatomic location, laterality, continuity, onset, complications, HLA-B27 status, and relative diagnostic certainty. Additionally, we reviewed all charts of patients diagnosed with TINU or with a presentation of uveitis that was typical of TINU (i.e., bilateral sudden-onset anterior uveitis). Prevalence of TINU in identifiable subsets of patients with uveitis, visual acuity (VA), and renal function. Individuals with TINU (n = 33) represented 1.7% of all patients with uveitis. However, TINU was diagnosed in 32 of the 316 patients (10%) presenting with bilateral sudden-onset anterior uveitis and in 20 of 62 of these patients (32%) who were younger than 20 years. Creatinine levels were more likely to be elevated in patients older than 40. Most patients maintained excellent VA and did not develop clinically significant renal impairment. Tubulointerstitial nephritis and uveitis syndrome is a common cause of uveitis among patients who present with bilateral sudden-onset anterior uveitis. The size of this series clarifies the understanding of the relationship between renal and ocular disease; facilitates recognition of the syndrome; and adds to the knowledge on prognosis, complications, and role of antecedent medications.