A study has been made of 39 patients with isolated fits presenting to an EEG department. Patients were excluded when there was a doubtful history, alcoholism, or drug abuse. The 39 patients were compared with a control group of patients with epilepsy matched for age and sex. No basic difference was found between the two groups. In particular the EEG examination showed similar changes. In conclusion, patients with isolated fits should be assessed in the same way as those with established epilepsy, while recognizing that in the majority of instances no serious underlying cause will be found.