We undertook two randomised studies in an effort to decrease the dosage of steroids in transplanted patients and to replace harmful steroid therapy by nonsteroid anti-inflammatory (NSAI) drugs. In the first study, 50 consecutive transplant recipients were randomly assigned to the treatment or the control group. In both groups, patients received azathioprine and prednisolone. ATG was added to this protocol in the experimental group. The number of renal failure episodes and consequently the amount of steroid necessary to control these episodes were significantly lower in the ATG group than in the other group. Two year post-transplantation kidney survival was 79% in the ATG group and 52% in the control group. In the second study, 15 consecutive transplant recipients were randomly assigned to two control groups and to one experimental group, where steroids were replaced by NSAI drugs. This preliminary, and very limited, pilot trial demonstrates the existence of early acute renal failure episodes, probably of immunological origin, which can improve spontaneously in the absence of steroid therapy.