Primary headaches (migraine, cluster, tension-type) are common disorders thought to be unrelated to nasal and sinus abnormalities. We present data on 19 patients with refractory primary headaches in the absence of significant sinus symptoms. The majority of patients responded with decreased pain to office application of nasal anaesthesia. A high prevalence of sinonasal abnormalities was found on coronal CT scans. Seventy-nine per cent responded with either decreased pain severity or headache frequency after endoscopic sinonasal surgery. We discuss possible underlying mechanisms to explain these findings.