Thirty-six patients with recurrent carcinoma of the head and neck and no prior exposure to chemotherapy were treated with Ifosfamide. This drug was administered, concomitantly with Mesna, as a 24-hr infusion at a dose of 5-6.25 g/m2 every 3 weeks. Objective activity in 32 evaluable patients was 28% (9/32, 95% C.I. 17%-39%); 40% of patients had leukocyte values less than 2000 mm3 and 6% platelets less than 50,000 mm3. Nonhematologic toxicity consisted mainly of nausea/vomiting (66% greater than or equal to grade 2) and alopecia (80% greater than or equal to grade 2). The activity encountered warrants further studies with this drug in head and neck cancer.