Prisms and Multiplicities shows how ignoring group contexts in many traditions of psychotherapy can distort descriptions of what happens in therapy, with serious unintended consequences. For example, identifying mothers alone as the effective ‘environment’ for their babies, makes mothers the fulcrum of mental health and wellbeing, thus ignoring how such culturally-bound childcare arrangements lead to ‘mother-blaming’ for the problems an infant may experience when growing up. The chapter shows how this narrowed vision ignores the workings of effective group-based therapies, sidelines the family dynamics which enfold infants, and denies infants’ subjective complexity. Such blindnesses suggest that the ‘attachment paradigm’ constitutes a self-validating ‘scientific’ community whose group dynamics render it oblivious to its own inadequacies. The strong resonance of attachment narratives in some professional circles invites analysis in terms of rhetoric, not science – as the chapter illustrates. It concludes by advocating approaches to assessment and therapy which honour the complexity of babies’ worlds.