This week saw the demise of one of the greatest figures ever in infancy research, and the person who really begun the process of linking developmental science and therapeutic practice. News of Daniel Stern’s death has shaken all who came into contact with him and who knew of his work. I am sure I am not the only person whose world was turned upside down when I first read what is still his best known work, The Interpersonal World of the Infant . It is quite extraordinary how far the field has come since the publication of that seminal book. Looking back at that text, it was clearly a work of genius, so far ahead of its time, and in it Stern put into words so much that so many people had faintly intuited but could not make explicit. It was Stern who first taught us about affect attunement, a concept we take for granted now but which he had to persuade us of. He did this using research and videos about real babies, showing us how they were born primed to interact, to seek out faces and voices, born ready to be understood, feelingful beings who were also extremely intelligent. Stern’s baby was a real baby, alive, flesh and blood, and researchable, and those of us working therapeutically needed the evidence he brought to put alongside the theoretical psychoanalytic babies we had been taught about, by Freud, Klein, Winnicott, Lacan and others. His was a mind which would not be confined and he embraced not only psychoanalysis and infancy research, but creative arts and especially music, to help make sense of processes of change and development.