We report our experience with the use of interstitial iridium-192 implantation in the management of patients with recurrent and locally advanced squamous cell carcinoma of the head and neck. Between June 1992 and July 1998 this technique was employed in the management of two groups of patients: (1) a primary group, comprising 42 patients who had presented for the first time with advanced head and neck disease, and had therefore not undergone any previous treatment; and (2) a salvage group of 16 patients with recurrent disease previously treated with external beam radiotherapy (four received therapy to the neck, one to the cheek, eight to the tongue and three to the floor of the mouth). The follow-up in each group was short, ranging from 3 to 56 months. The overall response in the primary group was 38/42 (90%). A complete response was achieved in 35/42 (83%). In the salvage group, the overall response was 13/16 (81%); 4/16 (25%) showed a complete response and 9/16 (56%) a partial response. The estimated percentage surviving at 1 year for patients with primary disease is 70% (95% confidence interval (CI) 54-86). For those receiving salvage therapy the estimated percentage surviving at 1 year is 45% (95% CI 19-71).