To confirm the findings of uncontrolled trials that methylprednisolone pulse therapy (MPPT) is a safe treatment for active rheumatoid disease, a double-blind trial was conducted in which 20 patients with active rheumatoid disease were randomly allocated to receive an infusion of either 1 g methylprednisolone or placebo. Methylprednisolone produced significant improvement in all clinical variables measured, a benefit which was sustained for at least 6 weeks. The placebo produced only transient improvement in some of the clinical variables measured. when the 10 placebo groups patients were later given an infusion of 1 g methylprednisolone, they too showed significant clinical benefit. The methylprednisolone also gave rise to improvements in some haematological and biochemical variables.