Generalized convulsive status epilepticus (GCSE) is a life-threatening emergency, and multiple agents have been advocated for the initial treatment. The VA Status Epilepticus Cooperative Study Group conducted a randomized, blinded trial comparing intravenous diazepam followed by phenytoin, lorazepam, phenobarbital, or phenytoin as first-line treatment for GCSE. In the intention-to-treat analysis, no significant difference in treatment was observed across all groups for patients with either overt GCSE or subtle GCSE. Among patients with verified-diagnosis overt GCSE, lorazepam was most successful at achieving cessation of seizures, though no difference was observed among patients with verified-diagnosis subtle GCSE. Results from this trial and two others establish benzodiazepines as the favored first line treatment of GCSE. Investigations are ongoing comparing benzodiazepines to newer antiepileptic drugs. The Established Status Epilepticus Trial will be the first randomized trial comparing fosphenytoin, levetiracetam, and valproic acid for benzodiazepine-refractory status epilepticus in children and adults.