Rheumatoid arthritis is a systemic disease of unknown etiology which has, as its most obvious manifestations, inflammation, dysfunction, and pain in joints, primarily the small joints of hands and feet, less often knees and elbows. There is a specific subcategory, gout, the cause of which is known: deposition of uric acid crystals in the joints, particularly of the great toe. The formation and excretion of uric acid can be controlled by allopurinol and probenecid respectively. Juvenile rheumatoid arthritis has a variety of onsets: polyarticular, monarticular, and acute febrile. Each has been described in detail in the body of this paper. Osteoarthritis, or degenerative joint disease, differs from rheumatoid disease in that it is not an inflammatory process nor has it systemic components. Treatment for all the described arthritic conditions consists of a persistent regular regimen of rest, mild exercise, and drugs, which together will control pain, prevent deformity, and maintain function in affected joints. If deformity has occurred, surgery is an effective means of restoring function or, in the case of arthrodesis, relieving pain and thus providing opportunity to achieve function in a modified manner.