In patients with refractory germ cell tumour who fail to achieve complete remission (CR) or which achieve CR but subsequently experience disease progression within 2 months of receiving cisplatin + vinblastine + bleomycin (PVB) the results of further treatment are poor. Similarly, third-line therapy after cisplatin with VP 16 salvage rarely produces clinically significant remission. From February 1983 to October 1984 we treated 53 patients with ifosfamide (1.2 g/m2 per day on days 1-5), VP 16 (75 mg/m2 per day on days 1-5), cisplatin (20 mg/m2 per day on days 1-5), and N-acetylcysteine (2.0 g p.o. every 6 h on days 1-7). This was repeated every 21 days for four to six cycles. One group of patients (group A, 20 pts) had achieved partial remission (PR) but still had nonresectable tumours after PVB therapy; a further group (group B, 4 pts) had achieved CR with PVB but then experienced disease progression within 2 months; the remaining patients (group C, 28 pts) had experienced disease progression after one or more salvage attempts, including therapy with cisplatin and VP 16. Of the original 53 patients, 51 were evaluable for response. Toxicity included moderate to severe myelosuppression in almost all patients, fever/sepsis in 8, creatinine greater than or equal to 6 mg% in 4, and hematuria in 4 patients. There were no drug-related deaths. CR was attained in 17/51 patients (34%), these being 8/20 in group A, 1/4 in group B, and 8/28 in group C, and 10 patients have remained in CR for periods ranging from over 1 month to over 17 months. PR was achieved in 20 patients (40%), but their median duration of remission was only 2 months. We feel these results, obtained in a poor-prognosis patient population, are sufficiently encouraging to warrant further study of this regimen, including investigation of its use as initial salvage therapy following PVB.