A survey of North American pediatric nephrologists was conducted to assess the variability in the treatment of primary steroid-resistant focal segmental glomerulosclerosis (FSGS) of native kidneys. The most widely used immunosuppressive drug was cyclosporin A, with 73.9% using it often or sometimes. Only 44.3% used intravenous methylprednisolone combined with an alkylating agent at least sometimes; the use of methylprednisolone without cytotoxic drugs was slightly more common. Prolonged oral steroid therapy (>3 months) was used often or sometimes by 50.3%. The use of angiotensin converting enzyme inhibitors was very common, while lipid-lowering agents were rarely used. The variability in the treatment of FSGS most likely results from lack of evidence-based information and underscores the need for controlled pediatric multicenter treatment trials.