After a 5 years' experience of cerebral sonography (about 4,500 recordings) in infants we are trying to establish correlations between alterations of anatomical structures and the further clinical development. Obviously there is no constant connexion between a simple subependymal haemorrhage and the further neurological symptoms. At the age of two and more years, about 30\% had a normal state, the other part had very different clinical signs. Even an uncomplicated ventricular haemorrhage had no definite influence on the child's development in most cases. Ischemic infarctions seem to have a better prognosis than borderline-infarctions. Real intracranial cysts and slight brain atrophy seem to have only distinct neurological symptoms. Porencephalic defects or brain necrosis, e.g. after parenchymatous haemorrhages and infarctions as well as generalized hypoxic encephalopathies with increased echogenicy and progressive brain atrophy nearly always showed neurological defects, though the dimension of the brain's alteration does not clearly correlate to the clinical symptoms and the child's development. It is not possible to make a prognostic evaluation by cerebral sonography in hypoxic-ischemic brain-lesions within the first 3 weeks post partum. A more exact judgement will be given after further regular sonographic observations in all high-risk infants within the first year. Beyond this, technical and organisation-improvements will probably allow a more exact statement in future.