This paper is in three parts—first, a review of psycho-analytic literature dealing with Christmas; second, a number of case studies and third, a discussion. The author presents the theory that the Christmas festival stimulates sibling rivalries with a predominantly oral colouring. For such patients the birth of Christ symbolizes the newly born sibling with whom they were unable to compete successfully. Such emotional problems result in depressive reactions. Unconscious wishes to obtain the penis by means of which they could obtain the mother's love were uniformly present in the cases described. The author suggests that all patients, whatever the clinical diagnosis, who suffer from Christmas depression will be found to present a similar psycho-pathology.