There are now three known causative genes for familial hemiplegic migraine and increasing evidence to support a genetic predisposition to the more common types of migraine with and without aura, and for cluster headache. We present the first reported case of familial hemicrania continua. A mother and daughter developed hemicrania continua at the same time of life. Both showed an absolute response to indometacin and at similar doses. Both also suffered from migraine with aura. We discuss the increasing support for a genetic predisposition to dysfunction of the pain system within the brain manifesting as primary headache.