The prevailing anatomical definition of the frontal lobe has resulted in a lobe that is heterogeneous with respect to structure, function and developmental features and at the same time splits up the motor and sensory cortices which have strong functional and developmental bonds, assigning them to different lobes. This topographical map also ignores disease patterns evidently related to developmental principles as illustrated by primary degenerative dementing disorders such as frontotemporal dementia and Alzheimer's disease. It is therefore suggested that the frontal lobe is restricted to prefrontal structures, in front of the precentral fissure, whereas the motor and sensory cortex together form a central lobe, posteriorly followed by the parietal lobe. These lobes thereby gain in anatomical, functional and developmental purity as well as with respect to disease patterns. This division, thus based on structure, function, phylogeny, ontogeny makes for a better understanding of topographic patterns shown by degenerative disorders.