One hundred and thirty-nine cases of metastatic carcinoma in the cervical lymph nodes from an unknown primary have been reviewed. It appears that external radiotherapy is effective in controlling local disease but the prognosis of these cases is poor as they represent disseminated disease at presentation. The crude survival rates at two and five years were 17 and 5% respectively and the overall median survival was nine months. There are no favourable prognostic signs, although there was a tendency for most long-term survivors to have a long duration of symptoms prior to hospital referral. Improved diagnostic techniques are required to elucidate the sites of the primary tumour in these cases. Computerised axial tomography may facilitate this and lead to a more radical approach to treatment.