BACKGROUND: The aim of this study was to compare imaging modalities for staging the neck in a prospective cohort of patients evaluated by CT, ultrasound with fine-needle aspiration cytology (FNAC), and [(18) F]fluoro-2-deoxy-D-glucose (FDG) positron emission tomography (PET)/CT with the histologic evaluation of the neck dissection as the standard of reference. METHODS: In all, 76 consecutive patients were prospectively enrolled. RESULTS: Ultrasound-guided FNAC showed the highest level of agreement with histology for exact N classification. Ultrasound-guided FNAC showed the smallest percentage of overstaged patients, 7%, versus 16% with PET/CT, 13% with CT, and 13% with ultrasound. The rate of understaged patients was comparable between the imaging modalities. With regard to the endpoint N0 versus N+ there were no statistically significant differences to be found. CONCLUSIONS: Ultrasound-guided FNAC seems to correlate best with histologic staging compared with PET/CT and CT. None of the modality is reliable enough to replace elective neck treatment in cN0 necks. © 2011 Wiley Periodicals, Inc. Head Neck, 2011.