reports of autopsies on infants known to have FAS. The first was in 1973, on an infant who died shortly after birth. The examination revealed extensive brain damage, including microcephaly, migration anomalies, callosal dysgenesis, and a massive neuroglial, leptomeningeal heterotopia covering the left hemisphere. In 1977, Dr. Clarren described a second infant whose mother was a binge drinker. The infant died ten days after birth. The autopsy showed severe hydrocephalus, abnormal neuronal migration, and a small corpus callosum (which connects the two brain hemispheres) and cerebellum. FAS has also been linked to brainstem and cerebellar changes, agenesis of the corpus callosum and anterior commissure, neuronal migration errors, absent olfactory bulbs, meningomyelocele, and porencephaly. Neurological When structural impairments are not observable or do not exist, neurological impairments are assessed. In the context of FASD, neurological impairments are caused by prenatal alcohol exposure which causes general neurological damage to the central nervous system (CNS), the peripheral nervous system, or the autonomic nervous system. A determination of a neurological problem must be made by a trained physician, and must not be due to a postnatal insult, such as meningitis, concussion, traumatic brain injury, etc. All four diagnostic systems show virtual agreement on their criteria for CNS damage at the neurological level, and evidence of a CNS neurological impairment due to prenatal alcohol exposure will result in a diagnosis of FAS or pFAS, and functional impairments are highly likely. Neurological problems are expressed as either hard signs, or diagnosable disorders, such as epilepsy or other seizure disorders, or soft signs. Soft signs are broader, nonspecific neurological impairments, or symptoms, such as impaired fine motor skills, neurosensory hearing loss, poor gait, clumsiness, and poor hand - eye coordination. Many soft signs have norm-referenced criteria, while others are determined through clinical judgment. "Clinical judgment" is only as good as the clinician, and soft signs should be assessed by either a pediatric neurologist, a pediatric neuropsychologist, or both. Functional When structural or neurological impairments are not observed, all four diagnostic systems allow CNS damage due to prenatal alcohol exposure to be assessed in terms of functional impairments. Functional impairments are deficits, problems, delays, or abnormalities due to prenatal alcohol exposure (rather than hereditary causes or postnatal insults) in observable and measurable domains related to daily functioning, often referred to as developmental disabilities. There is no consensus on a specific pattern of functional impairments due to prenatal alcohol