Sight threatening uveitis may require long term use of systemic immunosuppressants. In some patients, aggressive systemic immunosuppressive therapy fails to control inflammation and can lead to serious side effects. Oral Cyclosporin A (CsA) has been shown in several human trials to be effective in treating chronic uveitis. This pilot study will assess the safety, and to some extent efficacy, of a novel intraocular CsA release implant in patients with active inflammation and poor visual acuity in one eye despite immunosuppressant therapy. Patients will be randomly assigned to receive in one eye a 1 or 2 mg CsA implant releasing at either 0.8 microgram per day or 1.4 microgram per day respectively. The main purpose of the study is to assess the safety of the CsA implant. Secondary outcomes will include a change from baseline in the ocular inflammation, visual acuity, and the need for concomitant anti-inflammatory medications.