Hypnic headache syndrome is a benign, recurrent, late-onset headache disorder that occurs exclusively during sleep. It affects elderly men and women with a mean age of presentation of 60 years. Pathogenesis is poorly understood and a secondary cause can often be found in this age group. In this article, Drs Bhaskar Mukherjee and Francis Vaz discuss the differential diagnosis and management of hypnic headache in the elderly.