A prospective study is reported of antiepileptic drug withdrawal in 62 neurologically intact adult patients who had become seizurefree at least 3 years previously. No single clinical or laboratory finding was reliably predictive of outcome and in particular the presence of epileptiform EEG activity prior to AED withdrawal or appearance of such activity during withdrawal was not associated with relapse. A multivariate model was however developed which suggested that patients capable of remaining seizure-free without medication could be reliably identified at a much reduced cost of relapses in the remainder.