A study was conducted on the incidence of postoperative nontoxic goitre in 206 patients. The mean period of postoperative observation was 7.8 years. The recurrence rate was 30.7% in the 26 patients to whom thyroxine was administered regularly and at doses of 0.15 mg/day or more in the postoperative period, and 46.9% in the 32 patients who received thyroxine regularly at low doses (0.10 mg/day). In contrast, recurrence rate was 71.4% in the 49 patients in whom use of thyroxine was irregular and 81.8% in the 99 patients who received no thyroxine. The recurrence rate was markedly reduced in the patients who used thyroxine regularly at doses of 0.15 mg/day or more as compared with those who used it irregularly or not at all. It was concluded that in Turkey, where iodine deficiency is a major contributory factor of the prevalence of goitre, postoperative administration of thyroxine is necessary in order to reduce the postoperative recurrence rate.