An attempt has been made to evaluate critically the results of nutritional and, more particularly, vitamin studies, as they relate to the clinical syndromes of delirium tremens, the Korsakoff psychosis, Wernicke's syndrome and the various cerebral disorders that result from a deficiency of nicotinic acid. The manner in which chronic alcoholism may produce dietary insufficiency is briefly discussed. We emphasize the fact that while alcohol is apparently not immediately responsible for most of the observable damage, alcoholism is responsible for these changes. The effect of alcohol per se has still to be evaluated. We accentuate also the frequency with which these pictures merge one into the other, and the fact that vitamin therapy, to be effective, must be instituted before irreversible structural changes have occurred. As in vitamin deficiency diseases occurring elsewhere, those affecting the nervous system are usually the result of multiple rather than single deficiencies. A well balanced diet should therefore always supplement treatment with the specifically indicated vitamin or vitamins.It is our belief that future studies of the type here reviewed will yield much information of value to students of nervous economy.