Robert Langs had a substantial impact on American psychoanalysis in the 1970s and 1980s—both Freudian and Jungian —due to his development of what he termed “the adaptive paradigm.” According to Langs, the psychoanalytic tradition had vastly underestimated the clinical importance of adaptation, both the role adaptive problems play in psychological and emotional conflicts as well as the significance adaptation has for understanding unconscious communications in clinical practice. In spite of Langs’ impact on the psychoanalysis and analytical psychology of his time, there have been few psychoanalytic studies either of adaptation or of Langs’ adaptive paradigm since the 1980s and no attempts to link Langs’ thinking with that of Carl Jung. Adaption and Psychotherapy gives a concentrated but complete picture of Langs’ adaptive clinical theory and also expands Langs’ treatment of adaptation by examining Jung’s theory of adaptation. Jung offers an extended treatment of adaptation in his treatise On Psychic Energy. However, understanding Jung’s theory of adaptation is difficult, due to Jung’s having two diverse and virtually exclusive meanings of “adaptation” in his writings, rendering his thought on adaptation somewhat obscure and, at times, inconsistent. The book differentiates those diverse meanings of adaptation and articulates Jung’s positive and clinical understanding of adaptation in a way that allows comparison to Langs’ adaptive paradigm as well as a creative synthesis of the two approaches. The result is a development of Langs’ adaptive paradigm and an expansion of clinical theory and technique that is valuable for both Freudian and Jungian analysts.