Currently available treatments for psoriatic arthritis are either not completely effective or toxic in some patients. As tumour necrosis factor (TNF)-alpha is involved in both the joint and skin involvement in psoriatic arthritis, blockade of TNF-alpha seems a reliable way to treat patients with this disease. We report two patients with progressive recalcitrant psoriatic arthritis treated with low-dose methotrexate (7.5 mg, once per week) in combination with intravenous chimeric monoclonal anti-TNF-alpha antibody (infliximab, 3 mg/kg body weight). Both showed a dramatic and rapid response in the reduction of pain, followed by improvement of laboratory and clinical signs of joint inflammation. Skin disease also responds after a short delay. The observation shows that infliximab is effective and well tolerated in patients with recalcitrant progressive psoriatic arthritis. Different kinetics of symptom release during treatment suggest a variable role for TNF-alpha in disease pathways of pain, joint inflammation and skin involvement.