Cryptogenic epilepsy (epilepsy with no obvious cause) is the most common form of the disease in adults. The author discuss clinical- electroencephalographic, neuroimaging (magnetic resonance tomography, positron emission tomography, proton magnetic resonance spectroscopy, diffusion tensor magnetic resonance tomography) and treatment aspects of 70 patients with cryptogenic epilepsy. A dynamic study of patients using neuroimaging methods allowed to single out two groups of patients differed by the course, outcome and treatment. The author suggests hypotheses on the explanation of processes underlying epilepsy with no obvious cause.