This early work on Papers of Psycho-Analysis is both expensive and hard to find in its first edition. The papers here collected have already appeared in print, for the most part in psychological journals that do not circulate widely among the medical profession. They constitute a selection of the authors contributions, and are now issued in a more accessible form in the hope of arousing further interest in this overneglected and important branch of scientific investigation. Many of the earliest books, particularly those dating back to the 1900s and before, are now extremely scarce and increasingly expensive. We are republishing these classic works in affordable, high quality, modern editions, using the original text and artwork.