Carcinoma of unknown primary of the neck (CUP) is a metastasis presenting in one or more cervical lymph nodes, with no primary mucosal site identified. Retrospective case notes review of 25 consecutive patients (median age 55, 72% males) diagnosed as CUP who underwent neck dissection in a UK tertiary referral comprehensive cancer centre between 2000 and 2011. Median follow-up was 33 months. Nineteen patients underwent comprehensive neck dissections (six extended), six patients had selective neck dissection. Five year disease specific survival and regional recurrence free survival were 76 and 80% respectively. The overall rate of occult disease (disease not identified on preoperative evaluation, but found on histopathologic examination) was 8%, with rates of 0% in level I and 6% in level V. Our study suggests that in patients without preoperative evidence of disease in levels I or V selective neck dissection might be considered as an option, to facilitate preservation of the submandibular gland and accessory nerve without compromising oncological outcome. Larger studies should be performed before a change in practice can be advised.