The eye is commonly affected by many diseases evaluated by a rheumatologist. Uveitis, i.e. inflammation inside the eye, has a lengthy differential diagnosis, which includes many infections and systemic inflammatory diseases. This lecture will familiarize the audience with important causes of uveitis, which include infections such as tuberculosis, syphilis, CMV, toxoplasmosis, and herpes simplex; malignancies such as B cell lymphoma; and systemic diseases such as ankylosing spondylitis and sarcoidosis. Internists in general and rheumatologists, infectious disease specialists, nephrologists, oncologists, and neurologists in particular should understand uveitis in order to collaborate with ophthalmologists to improve the diagnosis and treatment of this group of diseases.