SPINAL involvement in rheumatoid arthritis in children has occasionally been noted in the literature, but never emphasized or adequately described. At the Robert Breck Brigham Hospital in Boston, an institution devoted largely to rheumatic diseases, we have for some time been impressed with the large number of cases of clinical spondylitis in these children. We have therefore undertaken a survey of all cases of juvenile rheumatoid arthritis seen over the past forty years, to determine the incidence and nature of the spondylitis. The older material has not always been adequate. Thanks to the formerly popular "focus-of-infection" search many x-ray films . . .