There is good, controlled evidence which suggests that cyclophosphamide, and perhaps related drugs, have a definite role in the treatment of nephrotic children with the minimal change lesion. This role is one of secondary treatment, and the drugs should not be used as a first line of attack; they should be employed only when corticosteroid resistance or toxicity is a problem. In a few patients, azathioprine or 6-mercaptopurine may have a role in minimising corticosteroid toxicity, but the remission induced in relapsing children is no more durable than that after corticosteroids. Chlorambucil must be given in doses, and for periods long enough to run the risk of neoplasia, particularly leukaemia; there does not appear to be a place for its use in nephrotic children unless the duration of remission can be shown to be longer than that obtainable with cyclophosphamide. There is no evidence that any immunosuppressive agent has a place in the management of children with idiopathic glomerular disease showing structural alterations in the glomeruli. Children with systemic lupus erythematosus and nephritis may benefit from the addition of cytotoxic agents to their corticosteroid regime, although the indications for this are not clear, and controlled evidence is lacking.