What are the consequences, if any, of repeated brief seizures that are the defining feature of epilepsy? A firm answer to this question has been surprisingly elusive for a variety of reasons. Clearly there is a subset of patients who appear to tolerate seizures with relatively limited long-term consequences, and not all patients are destined to progress to intractability with frequent seizures and disability. This variability and individual susceptibility has made it difficult to make statements that fairly apply to the full range of people with epileptic disorders, whose disorders span a broad spectrum from mild with excellent control and few limitations, to severe with multiple daily seizures and pronounced disability that affects employment, educational performance, an personal life. This volume seeks to explore the spectrum of severe to more subtle damage that may be a consequence of seizures. The contributing authors have addressed these questions and related issues using a variety of methods in experimental models and in patients with epilepsy.