A Phase II pilot study of continuous hyperfractionated accelerated radiotherapy (CHART)/CHART weekend less (CHARTWEL) was carried out in the postoperative treatment of patients with squamous cell carcinoma of the head and neck. Twenty-four patients (17 male, seven female) with a median age of 64 years (range 34-80) were treated with postoperative radiotherapy between 1991 and 1999. All patients presented with primary squamous cell carcinoma, which, at surgery, had shown adverse pathological factors for recurrence. Intermediate risk was determined by the presence of two of the following factors: margins 5 mm, Stage T3/T4, perineural or vascular invasion, poor differentiation, oral primary, multicentric primary, and more than four positive lymph nodes. High-risk factors included the presence of extracapsular spread and/or incomplete resection margins, or the presence of four of the factors defining intermediate risk. The patients were treated using a CHART (n = 11) or a CHARTWEL (n = 13) schedule, administering a dose between 49.5 Gy and 54 Gy. High-risk factors were present in 18/24 patients. Treatment was commenced from a median time of 6.9 weeks (range 4.4-16.6) after radical surgery. All patients completed treatment. A confluent radiation mucositis occurred in 20/23 evaluable patients, which settled in 4-10 weeks after commencing radiotherapy. Moderate dysphagia was observed in 13 patients. Mild subcutaneus oedema was noted in 11 patients from 12 weeks after treatment. No significant late toxicity has been observed. Over a median follow up-period of 17 months, local control has been maintained in 17 patients (71%). Seven patients have relapsed and died of disease. A mean survival of 24 months (range 1-84) has been observed. This pilot study demonstrates acceptable morbidity for CHART/CHARTWEL in the postoperative setting. A prospective multicentre randomized trial using an accelerated schedule of radiotherapy versus conventional fractionation for the radical postoperative treatment of primary head and neck cancer is currently in preparation.