Purpose of Review <p>Ketogenic diet therapies are a major, nonpharmacologic method of treating epilepsy, typically when highly refractory. This review examines the indications for ketogenic diet therapies, types of diets, methods of initiation, aspects of management and follow-up, practicalities of fine-tuning, adverse effects, interactions with antiseizure medications, and lastly discontinuation.</p> Recent Findings <p>Multiple studies have identified strong evidence for benefit for several epilepsy conditions (including Glut-1 deficiency syndrome, pyruvate dehydrogenase deficiency, infantile spasms epilepsy syndrome, super-refractory status epilepticus, and epilepsy with myoclonic atonic seizures). Consensus guidelines exist for overall management, use in infants, adults, those with Glut-1 deficiency syndrome, and patients with epilepsy in countries with limited resources.</p> Summary <p>Ketogenic diet therapies are a valuable, effective method of treating refractory epilepsy in children and adults. Neurologists must be aware of these treatments, especially with their continued expansion into the treatment of neurologic conditions other than epilepsy.</p>