The incidence of non-convulsive status epilepticus (NCSE) in The Netherlands is not known. Files of admissions in the years 1980-7 were studied from 40 adult patients (older than 15 years) with complex partial status epilepticus (CPSE) and 25 with absence status epilepticus (ASE). The clinical presentation sometimes made distinction between CPSE and ASE possible. Focal clinical signs were more frequent in CPSE; a fluctuating level of consciousness was more often present in ASE. All patients, but one, with ASE and most patients with CPSE (28) were known to have had previous epilepsy. Outcome in ASE was good in all. Outcome in CPSE depended on the underlying cause and quality of treatment. In three patients inadequate treatment probably contributed to morbidity.