In complex partial crises (CPC) some characteristics of the way in which they occur may be helpful in localizing the focus of origin in the cerebral cortex. Thus, the appearance of any kind of status epilepticus will not predominate depending on the origin of the epileptic focus, but the complex partial state will be rare when the origin is temporal and more frequent when the origin is frontal. The appearance of CPC in a cluster form is, on the other hand, characteristic of crises originating in the frontal lobe.We review the clinical history of 151 epileptics with CPC, evaluating the way in which the crises appear, together with other clinical data. We define the start of the crisis in a specific lobe, when this was the site of maximum voltage of the epileptic anomaly or of maximum phase opposition.10% of the patients showed grouping of their CPC; in the remainder the appearance was isolated, 15% showed status epilepticus at some point in their illness. We found a statistical difference when relating this to the anomalous topography of the EEG; between 15% and 42% more patients with status epilepticus were counted when the topography of the anomaly in the EEG was extratemporal. There was also between 37.2% and 76.4% more patients with cluster crises in the cases with an extratemporal focus.