Pulse therapy with cyclophosphamide was administered to 44 patients with chronic glomerulonephritis of the nephrotic type with different morphological varieties. The treatment was effective in 59% of cases including 11 out of 24 patients resistant to oral treatment with immunosuppressors. The treatment results were better in patients with normal blood serum creatinine and normal arterial pressure. Remission of the nephrotic syndrome could be observed in mesangioproliferative glomerulonephritis, mesangiocapillary glomerulonephritis, mesangial glomerulonephritis and focal-segmentary hyalinosis. In fibroplastic nephritis, remission of the nephrotic syndrome was recorded in none of the cases. The only prognostically significant sign predicting the treatment effect was the activity index--the totality of the morphological signs reflecting nephritis activity. The sclerotic changes produced no significant effect on the treatment outcome.