Cluster headache, an excruciating, unilateral headache usually accompanied by conjunctival injection and lacrimation, can occur episodically or chronically, and can be difficult to treat. Existing effective treatments may be underused because of underdiagnosis of the syndrome. Oxygen and sumatriptan have been demonstrated to be effective in the acute treatment of cluster headaches. Verapamil has been shown to be effective for prophylaxis. For cluster headache completely refractory to all treatments, surgical modalities and newer interventions such as the implantation of stereotactic electrodes may be useful. Patients should be encouraged to avoid possible triggers such as smoking or alcohol consumption, especially during the duster period. The intensity of duster headache pain leads to ethical concerns among researchers over the use of placebo, making randomized controlled trials difficult. As new technology and genetic studies clarify the etiology of duster headache, it is possible that more specific therapies will emerge.