The steps taken for the discovery of the hallucinogenic effects of N.N-Dimethyl-tryptamine (DMT) is described. DMT had a difficult first 50 years in medical research primarily for legal reasons as it was classified as one of the "drugs of abuse" by authorities in the USA and by the World Health Organization. It has not proved to be a "schizotoxin" as it was first suspected, but the book is not closed on its potential role in some other, high level function as an endogenous neuromodulator. Further clinical work may even substantiate its usefulness in therapeutic application, such as an adjunct to psychotherapy, perhaps not by itself, but in a modified form, or in combination with other substances.