Epilepsy is the most common serious primary disease of the brain, accounting for 1% of the global burden of disease. Diagnosis and treatment suffer from a lack of reliable biomarkers for either epileptogenicity, the presence and severity of an epilepsy condition, or epileptogenesis, the development and progression of an epilepsy condition. The identification of reliable biomarkers would greatly facilitate differential diagnosis, eliminate the current trial-and-error approach to pharmacotherapy, facilitate presurgical evaluation, and greatly improve the cost-effectiveness of drug discovery and clinical trials of agents designed to treat, prevent and cure epilepsy. Identification of reliable biomarkers of epileptogenicity and epileptogenesis for research and clinical applications is a high-priority goal for the epilepsy community. Recent advances in electrophysiology, neuroimaging, molecular biology and genetics promise to reveal clinically useful biomarkers for epilepsy in the near future.