More than 30% of epilepsy patients are not controlled by anti-epileptic medications. For patients having intractable epilepsy, epilepsy surgery is an effective treatment, which provides not only control of seizures but also improvement of quality of life. Epilepsy surgery can provide complete seizure control in over 60% of patients having medically intractable epilepsy. In order to identify surgical candidates, various diagnostic modalities are being used. The value of video-EEG monitoring and MR imaging study cannot be over-emphasized. For certain circumstances, other diagnostic modalities, such as PET, SPECT, and MEG, provide complementary data. If the findings from these non-invasive studies collectively indicate that the patient can benefit from surgery, surgical resection can be performed. However, if the findings do not, invasive studies should follow. New surgical modalities for the treatment for epilepsy have been developed, including surgical resection of epileptogenic zone or lesion, disconnection of epileptogenic zone from the surrounding normal brain, and neuromodulation, such as vagal nerve stimulation, deep brain stimulation, etc. Also, newly emerging diagnostic modalities, such as high tesla MR imaging, magnetoencephalography or brain mapping technology, can help select surgical candidates more easily in the near future.