The young psychiatrist from Budapest had studied medicine in Vienna, he had read The Interpretation of Dreams, and now he was about to meet its author. Seventeen years Sigmund Freud's junior, Sándor Ferenczi (1873-1933) sent off a note anticipating the pleasure of the older man's acquaintance--thus beginning a correspondence that would flourish over the next twenty-five years, and that today provides a living record of some of the most important insights and developments of psychoanalysis, worked out through the course of a deep and profoundly complicated friendship. This volume opens in January of 1908 and closes on the eve of World War I. Letter by letter, a "fellowship of life, thoughts, and interests" as Freud came to describe it, unfolds here as a passionate exchange of ideas and theories. Ferenczi's contribution to psychoanalysis was, Freud said, "pure gold," and many of the younger man's notions and concepts, proposed in these letters, later made their way into Freud's works on homosexuality, paranoia, trauma, transference, and other topics. To the two men's mutual scientific interests others were soon added, and their correspondence expanded in richness and complexity as Ferenczi attempted to work out his personal and professional conflicts under the direction of his devoted and sometimes critical elder colleague. Here is Ferenczi's love for Elma, his analysand and the daughter of his mistress, his anguish over his matrimonial intentions, his soliciting of Freud's help in sorting out this emotional tangle--a situation that would eventually lead to Ferenczi's own analysis with Freud. Here is Freud's unraveling relationship with Jung, documented through a heated discussion of the events leading up to the final break. Amid these weighty matters of heart and mind, among the psychoanalytic theorizing and playful speculation, we also find the lighter stuff of life, the talk of travel plans and antiquities, gossip about friends and family. Unparalleled in their wealth of personal and scientific detail, these letters give us an intimate picture of psychoanalytic theory being made in the midst of an extraordinary friendship.