The lack of insight in schizophrenia has so far been interpreted as a primary symptom of the illness, namely a defensive mechanism rather than a neurologically-based condition. However, recent findings have emphasized its relationship with damage to specific brain areas as well as the domain specificity in which it may occur. This supports a neuropsychological interpretation of the lack of insight in schizophrenia. The present article reviews the foregoing data, and takes into account the most relevant anatomo-clinical results. There is evidence that the lack of insight in schizophrenia may occur as a neurological disease per se following brain damage that seems related to frontal lobe areas. Additionally, it could either be related to all aspects of the disease or be domain-specific, occurring for one kind of symptom but not for others. These data indicate several analogies with the phenomenon called anosognosia for a neurological deficit.