Purpose: Full-dose reirradiation combined with chemotherapy has been shown to be feasible after salvage surgery with acceptable toxicity. The Groupe d’Etude des Tumeurs de la Tête et du Cou and Groupe d’Oncologie Radiothérapie Tête Et Cou groups performed a randomized study to assess its efficacy. Patients and Methods: Between 1999 and 2005, 130 patients with head and neck cancer were treated with salvage surgery and randomly assigned to full-dose reirradiation combined with chemotherapy (RT arm) or to observation (a “wait and see” approach; WS arm). Eligibility criteria were recurrence or a second primary tumor in a previously irradiated area, no major sequelae resulting from the first radiotherapy, good general condition, no distant metastasis, and salvage surgery with macroscopic complete resection. Patients in the RT arm received 60 Gy over 11 weeks combined with concomitant fluorouracil and hydroxyurea. Results: Sixty-five patients were randomly assigned to each arm. There was no imbalance in the distribution of the main tumor and patients characteristics. The most serious acute toxicity in the RT arm was mucositis, attaining grade 3 or 4 in 28% of patients. At 2 years, 39% of patients in the RT arm and 10% in the WS arm experienced grade 3 or 4 late toxicity according to Radiation Therapy Oncology Group criteria (P = .06). Disease-free survival (DFS) was significantly improved in the RT arm, with a hazard ratio of 1.68 (95% CI, 1.13 to 2.50; P = .01), but overall survival (OS) was not statistically different. Conclusion: Full-dose reirradiation combined with chemotherapy after salvage surgery significantly improved DFS, but had no significant impact on OS. An increase in both acute and late toxicity was observed.