Stroke units are monitoring centers providing for acute diagnostic work-up, immediate treatment and initial rehabilitation measures in patients suffering a stroke. Indications for admission to a stroke unit are, firstly, a suspected fresh stroke or a transient ischemic attack, provided the symptoms are not older than 24 hours, and, secondly, progressive, unstable symptoms. A major aspect of the stroke unit is the establishment of a differential diagnosis, which provides the basis for establishing the urgent treatment of an apoplectic attack. The goal is to prevent the progression of symptoms, which occurs in one-third of patients and leads to permanent sequelae. Using a number of cases, the activities of a stroke unit are described. To improve the acute management of such patients, a close network of regional and national stroke units needs to be put in place.