Seventeen of eighteen patients hospitalized for active rheumatoid arthritis completed a three-day randomized, double-blind comparison of 100 mg indomethacin, 100 mg indomethacin with 10 mg diazepam and matching placebo as night medication. The results showed a consistent pattern in the four functions measured--pain, morning stiffness, sleep score and patient preference. In each, indomethacin proved superior to placebo and the combined therapy better than indomethacin alone. From this it has been concluded that the combination of indomethacin and diazepam should now be considered the treatment of choice for maximum control of night pain and morning stiffness in rheumatoid arthritis.