On 30 March, 1966, at the Symposium “Enzymes in Mental Health” sponsored by the Carl Neuberg Society for International Scientific Relations, A. Hoffer (1) described the apparently successful treatment in 13 of 17 (acute and chronic) schizophrenic patients in 3 to 5 days by the daily oral use of 1 to 2 grams of nicotinamide adenine dinucleotide (NAD), better known as diphosphopyridinenucleotide (DPN). Widespread publicity given to this announcement attests to the need of more effective treatment for this illness. It also occasioned frequent and persistent inquiry from schizophrenic patients and their relatives as to the suitability of this treatment in their own instance. Rapid confirmation of the findings would justify widespread efforts to evaluate this preparation, whereas failure of confirmation would provide reasonable grounds for a more cautious approach to its use. The members of the Council of the American College of Neuropsycho-pharmacology decided that, as a group of impartial scientists, it would be appropriate for them to carry out such an investigation as rapidly as was compatible with adequate determination of the usefulness of the preparation.