An epilepsy work up is most often initiated to characterize the seizures that the person with recurrent seizures presents with. Selecting the best medication for a particular seizure type or epilepsy syndrome requires such an understanding of the epilepsy. And when the patient is refractory to the medications, that is, the medications do not completely control the seizures, then the epilepsy work up becomes important to determine if surgery might be beneficial.

Video EEG monitoring is the best way to characterize the seizure syndrome since it is essentially the only way to capture an actual seizure.

Other modalities, such as MRI (describes brain anatomy), SPECT scan (describes brain blood flow), PET scan (describes brain metabolism of glucose), MEG (describes brain magnetic fields), intracarotid amytol study or Wada test (describes language laterality and quantifies short term memory function of the brain), neuropsychological testing (describes functional capacity of brain abilities and relates them to the locations they are likely to be found), functional MRI and MRI spectroscopy also help to characterize specific characteristics of a brain state and also help answer the two important questions related to epilepsy surgery (where are the seizures originating and is it safe to remove).

These studies are all circumstantial, in that they do not actually 'see' the seizure process within the brain, though Video EEG monitoring does 'see' a brain's electric field associated with a seizure. Still, this circumstantial evidence can often consistently point to a particular kind of epilepsy that helps to determine the best kind of medical or surgical management options for the particular patient.