The administration of certain drugs to patients with established rheumatoid arthritis frequently results in improvement that is slow to appear but persists for long periods, even after the drug is discontinued. The three main drugs with this effect, whose efficacy and toxicity are reviewed in this paper, are gold salts, D-penicillamine and chloroquine. The cytotoxic agents used to treat rheumatoid arthritis, which likely have nonspecific anti-inflammatory actions and have serious long-term side effects, are also briefly reviewed. A new drug, levamisole, is currently being tested in patients with rheumatoid arthritis. It is suggested that the time for considering the introduction of a remission-inducing drug in patients with progressive rheumatoid arthritis is after an adequate trial of therapy with salicylates or other nonsteroidal anti-inflammatory agents, or both, and before the oral administration of steroids. It is difficult, however, on the basis of rigorous clinical comparisons, to recommend which of the three main remission-inducing drugs should be tried first, although gold salts have been used the most. Patients who have improved with 6 months of chrysotherapy may continue treatment for at least 3 years, during which time the frequency of mucocutaneous and renal toxic effects will steadily decrease. Some aspects of the medical economics of therapy with remission-inducing drugs for rheumatoid arthritis are discussed.