The case of a child is described who at the age of 2 years showed the first evidence of a developing neurological disease. Within a couple of years, profound mental retardation and severe motor deficit with spastic tetraplegia became established. No seizures and no pigmentation of the retina were observed. The condition remained practically unchanged for some 8 years and the patient died at 12 years of age of terminal bronchopneumonia. At autopsy there was conspicuous diffuse atrophy of the brain. The cerebral cortex was particularly involved. Most of the cortical neurons were destroyed and neuroglia showed abundant proliferation. The few remaining neurons contained inclusion material which was identified as lipofuscin. Noticeable cedifferences from the various types of amaurotic idiocies are noted and similarities to a case of lipidosis recently reported from Finland are suggested.