Idiopathic crescentic glomerulonephritis (GN) often presents with a rapid loss of renal function and pathology showing extensive crescent formation. The disease is caused by different immunopathogenetic mechanisms, pauci-immune, often antineutrophil cytoplasmic antibody (ANCA)-positive microvasculitis, antiglomerular basement membrane (GBM) antibody disease, and immune complex formation. Historical reviews reveal poor renal prognosis, even after treatment with oral steroids and cytotoxic drugs. Prognosis has improved in the last decade. In this article, evidence-based recommendations for management are presented. Because of the high risk of end-stage renal disease (ESRD), early aggressive therapy is recommended, despite weak supporting evidence. Treatment for anti-GBM antibody-induced crescentic GN should be initiated early and should include pulse methylprednisolone, a two-week course of plasmapheresis and two months of treatment with corticosteroids and cyclophosphamide (grade B and C). Treatment for pauci-immune crescentic GN should be pulse methylprednisolone, followed by oral corticosteroids and cyclophosphamide for 6 to 12 months (grade B). Recurrences can be managed similarly (grade B), along with appropriate supportive therapy. In patients who develop ESRD, successful transplantation can be performed. Diffuse endocapillary proliferative GN is classically postinfectious. It generally has a good prognosis when no crescent formation occurs. Adult patients with persistent proteinuria, hypertension, and renal function impairment need careful follow-up and management to modify progressive hemodynamic injury.