Jenseits des Lustprinzips (Beyond the Pleasure Principle), first published in German in 1920 is an essay by Sigmund Freud marking a major turning point in his theoretical approach. Previously, Freud attributed most human behavior to the sexual drive (Eros or libido). With this essay, Freud went "beyond" the simple pleasure principle, developing his theory of drives with the addition of the death drive.
The essay is a detailed exploration of several concepts such as repetition compulsion, pleasure principle, the death drive, the nature of psychic energy, principle towards stability, the nature of drives and it is also a precursor to many further developments, such as a deeper study of masochism, or the study of anxiety.
The text is also important in Freud's distinguishing his position against Jung's theory of libido.