Recombinant interferon (IFN) gamma was used in 10 patients, 6 to 15 years old, with juvenile chronic arthritis (JCA) for 5 to 11 years, resistant or with severe side effects to other treatments. Six patients had systemic JCA and 4 started as pauciarticular. Three of the latter became polyarticular. Treatment schedule was 50,000 IU-kg daily for 4 weeks, then 3 times per week for 3 months and twice a week up to 2 years. Eight cases had favourable clinical response. Prolonged steroid regime could be suspended in 7/8 cases who previously received it. Two patients with systemic JCA did not respond to IFN treatment. Side effects were fever (9), headache (8), chills (6), distal cyanosis, hypotension, leukopenia and myalgia (2), and vomiting (1). All were mild or moderate. IFN gamma was more tolerable than other drugs and seems to be beneficial for patients with JCA resistant to other treatments.