The aim of this book has been to show how the Meaning of the Child Interview (MotC) assesses parent-child discourse and utilises it to understand relationships and plan intervention. This chapter focusses on the ‘why?’—what is it that the MotC is doing differently, and what is it offering the world of child and family welfare? The chapter briefly summarises research conducted on and with the MotC, as a springboard to outline three principles the MotC weaves together in a unique way. These are: None of these principles are new in themselves, and the MotC leans heavily on the work of others. The MotC, however, operationalises them practically in a path for practitioners to use and follow. If put into practice, this perspective profoundly challenges how professional systems and institutions operate, and how attachment theory is commonly applied in work with children and families.