This preface is an expression of Dr Adler's warm regard for Jung's special talent for communicating with people from all walks of life and at all psychological levels. This talent comes through in his letters, though it is not so evident in the main body of his work and writing.

Despite the difficulties of choosing from such a massive collection of letters, Adler clearly feels that his own selection, so far as is possible, conveys the essence of Jung's unique spirit.