Freud's early paper Psychical (or mental) treatment, first published in a family reference book for educated lay persons, was reproduced in the Gesammelte Werke with a stated publication date of 1905. This date was subsequently called into question owing to certain parts of the subject-matter (the use of hypnosis and suggestion in ‘mental treatment’), and the contribution was erroneously assigned, for instance by James Strachey, to the year 1890. This error is corrected in the present paper. Furthermore, the existence of a second edition of this reference book, which contains an addition to Freuds text and appeared in 1918-19, has previously gone unnoticed. The first edition had been published in 1905-6. Freud's contribution must, however, have been written at an appreciably earlier date. The probable time of its genesis is discussed. Freud's new text is reproduced (in English translation) for the first time in an appendix to this paper.