Despite introduction of new antiepileptic drugs the established drugs phenytoin, carbamazepine and valproate still provide the treatment of choice in most forms of epilepsy, being efficacious in approximately two-thirds of all newly referred patients. In 20-60% of patients resistant to treatment with the older drugs, a 50% reduction of seizure frequency can be achieved by adding ethosuximide, clobazam, vigabatrine, oxcarbazepine, lamotrigine, felbamate, tiagabine or topiramate to the classic treatment. The majority of the new drugs are free of the problematic enzyme induction of the older compounds, making monotherapy as well as combination therapy much easier. To what extent the new antiepileptic drugs are going to be used for the treatment of patients with epilepsy will depend on the analysis of cost and benefits. This will be based on efficacy, side effects, interactions and teratogenicity of these new compounds.