How is practical progress possible in child psychology and psychiatry? How does science advance to promote therapeutic innovation? The importance of the exciting stuff – new insights and ideas, studied using cutting edge and innovative technologies – is self‐evident. However, the philosophy of science has shown us that less obvious and more mundane elements are also essential. This is because scientific progress is only possible where attempts to break new ground are solidly anchored in a stable shared framework of assumptions – a metatheory – about the general nature of the phenomenon being studied. This framework defines what questions are considered ‘scientific’ – questions that it ‘makes sense’ to ask from a scientific point of view and those that are considered out of bounds (scientists with less subtle minds even considering such to be nonquestions rather than different sorts of questions). Kuhn called this framework a paradigm and the research activity that originates from it, normal science (Kuhn, 1962, The Structure of Scientific Revolutions; Princeton, NJ: Princeton University Press). These frameworks also serve a vital regulatory function because they contain common concepts that embody shared points of reference that allow scientists to communicate with each other to share their ideas, hypotheses and findings (Habermas, 1979, Communication and the evolution of society; Boston: Beacon Press).