Reviewed in this study are 40 patients treated by high-doses of alkylating agents followed by autologous marrow rescue for ovarian cancers. All patients received this therapy after extensive surgery and a median of 6 cycles of CDDP containing regimens (CAP or CHAP). All patients, except 4, who showed evidence of progression, had a second surgical exploration before the high dose chemotherapy. Conditioning regimens consisted of: melphalan at a dosage greater than 140 mg/m2 for all patients; in addition, 2 received Endoxan 120 mg/kg and 1 busulfan 16 mg/kg. Autologous marrow rescue was infused 24 h after the conditioning regimen. Severe, but reversible aplasia and mucositis were the most common toxicities. Three patients died from this procedure, 2 from infection and 1 from secondary leukemia. Twelve out of 15 patients evaluated responded (80%) showing evidence of activity in patients who did not respond to first line chemotherapy. Duration of response was short, especially for patients treated for progressive disease rather than in partial or complete response at the time of high doses chemotherapy. With a median follow up of 23 months (range 8.54) 19 patients survived (15 with non-evolutive disease) leading to a projected survival rate of 39% between 27 months and 5 years. These results are encouraging for poor risk patients who failed to respond to initial chemotherapy. For patients who have small or no residual disease after initial therapy, the place of such intensification should be confirmed prospectively in a larger cohort of patients.