From the Introduction by Daniel Benveniste: Psychoanalysis is a human tradition passed on from one generation to the next. This collection of letters and related documents are a testament to the fertile collaboration between Anna Freud and Humberto Nágera, and through these documents we witness the passing of the torch. Their work together was based at the Hampstead Clinic in London, and included clinical work, theoretical seminars, research, and cooperation in the management of administrative tasks at the Clinic. When Dr. Nágera informed me of this collection of letters, I immediately recognized that they documented one of the most fertile periods in Anna Freud's career, and were, therefore, worthy of inclusion in the literature on psychoanalytic history. I was honored to take on the editorial task, and found Dr. Nágera very helpful in answering my questions about people and places mentioned in the letters. I found, embedded in these letters and documents, keys to understanding the relationship between Anna Freud's personality and her work, which developed in the context of her relationships with others. A history of this kind presents the major contributor to psychoanalysis not as a larger-than-life person, but as a dedicated and gifted analyst working within an historical context and professional environment. Humberto Nágera was born in Cuba in 1927, and did his undergraduate work at the University of Havana, and his medical studies at Havana Medical School (1952). After becoming a psychiatrist he sought psychoanalytic training, and began as a psychoanalytic candidate at the Institute of the British Psychoanalytical Society in 1958, and a trainee at the Hampstead Clinic in 1959. Soon after his arrival at the Hampstead Clinic he became a trusted colleague of Anna Freud and collaborated with her as one of her closest associates during one of the most productive periods of her life. He left London and the Clinic in 1968, but maintained his correspondence with her until her death in 1982. What we learn from these letters and related documents is a bit about Anna Freud's personality: her shyness, her drive to work; her pursuit of knowledge; her collaborative spirit; her disappointments; her commitment to children, and her tireless and unwavering dedication to psychoanalysis. This collection of letters brings into high relief Anna Freud's work in the 1960s and in this way stands as a companion volume to the various biographies and collections of Anna Freud letters that have already been published. These naturally include: Raymond Dyer's The Work of Anna Freud (1983), Elizabeth Young-Bruehl's Anna Freud: A Biography (1988), Rose Edgecombe's Anna Freud: A View of Development, Disturbance and Therapeutic Techniques (2000), Peter Heller's book Anna Freud's Letters to Eva Rosenfeld (1992), covering the period from 1927 to 1932, Ingeborg Meyer-Palmedo's The Sigmund Freud, Anna Freud Correspondence 1904-1938(2013), and my own work, The Interwoven Lives of Sigmund, Anna and W. Ernest Freud: Three Generations of Psychoanalysis (2015).