Since December 1999, 3 drugs have been cleared for marketing by the US Food and Drug Administration for the treatment of partial-onset seizures in adults with epilepsy − levetiracetam, oxcarbazepine and zonisamide. All are approved as adjunctive therapy; oxcarbazepine is also approved as monotherapy. Levetiracetam appears to have a novel mechanism of action, while the others block voltage-sensitive sodium channels (oxcarbazepine and zonisamide) and T-type calcium channels (zonisamide). Levetiracetam and oxcarbazepine have short serum elimination half-lives and can be started at therapeutic dosages. All 3 drugs exhibit linear pharmacokinetics and have a low propensity for drug-drug interactions. There is extensive worldwide experience with oxcarbazepine and zonisamide, whereas exposure to levetiracetam has been limited to a relatively small number of patients in clinical trials.These 3 drugs are important additions to the armamentarium for the treatment of seizures and offer patients whose lives are compromised by epilepsy the potential to achieve a better quality of life.