Idiopathic intracranial hypertension (IIH) is a challenging disease characterized by an increase in intracranial pressure which occurs without any known cause. The disease is mainly seen in obese females of child-bearing age. While originally described as rare, the incidence is increasing in parallel with pandemic obesity, and clinicians in all fields are increasingly likely to meet patients with IIH. The condition causes major morbidity due to chronic headache and visual loss if untreated. In the past ten years new diagnostic criteria and guidelines for management have been published.