Clinical neurological involvement at various times throughout the illness was recorded in 52% of 122 patients seen in central London who died from acquired immunodeficiency syndrome (AIDS). Various metabolic encephalopathies, dementias, focal encephalopathies, retinopathies and peripheral nerve pathology were the most frequent manifestations. Seven of 9 patients with a neurological presentation had no other major systemic illness. The median time from diagnosis of AIDS to death was 9 months and from onset of neurological symptoms to death 4 months. Human immunodeficiency virus dementia, central nervous system opportunistic infections, presence of Kaposi sarcoma, neurological presentations and minor symptoms were not associated with major change in survival time.