In a study to investigate the efficacy and toxicity of long-term methotrexate (MTX) therapy in children with chronic arthritis, the medical records of 26 children (seven boys and 19 girls) with juvenile rheumatoid arthritis (JRA) were reviewed retrospectively. The patients received MTX therapy for a mean of three years (range, six months to six years). A clinically significant response occurred in 19 children (73.1%): remission in ten (38.5%) and improvement (25% reduction in the number of actively inflamed joints) in nine (34.6%). Concomitant prednisolone therapy was reduced in 13 out of 14 children (93%). Haemoglobin levels and erythrocyte sedimentation rates were statistically significantly improved over baseline after MTX therapy. Six (23%) children experienced toxic effects during MTX therapy. One patient discontinued the MTX treatment after 18 months because of jaundice and raised liver enzymes. It is concluded that the study confirms the efficacy, and acceptable toxicity profile, of MTX given over a period of several years to children with JRA.