He would become one of the most important poets of the twentieth century; she a muse of Europe's fin-de-siècle thinkers and artists. In this collection of letters, a finalist for the PEN USA translation award, the poet Rainer Maria Rilke and Lou Andreas-Salomé, a writer and intellectual fourteen years his senior, pen a relationship that spans thirty years and shifting boundaries: as lovers, as mentor and protégé, and as deep personal and literary allies.