The most recent studies, using the actuarial life-table technique, of the problem of long-term renal outcome and the factors that influence it in adult patients with one of the three most common types of chronic idiopathic immune complexes-mediated glomerulonephritis (IgA nephropathy [IgAN], membranous nephropathy [MN], and type I membranoproliferative glomerulonephritis [MPGN]) are reviewed. In the last decade, renal survival 10 years after onset has become similar to adult patients with idiopathic IgAN (80% to 87%) and idiopathic MN (75% to 83%), because of improvement of the renal survival of patients with MN. Renal survival at 10 years is worse for adult patients with idiopathic type I MPGN (60% to 64%). There is no substantial difference in the average renal survival times between different geographical regions, with the exception of a better prognosis for idiopathic MN in Japan. The presenting clinical factors that most strongly predict subsequent poor outcome are similar for the three types of glomerulonephritis and are rather nonspecific: (1) severe proteinuria, (2) impairment of renal function, and (3) arterial hypertension. As for the histological features, the most powerful predictor of subsequent progression in all three types of glomerulonephritis is tubulointerstitial damage, suggesting that a cell-mediated immune process believed to occur there may independently influence outcome in glomerular diseases.