This chapter extends on the previous one by investigating the validity of preexisting theories of intersubjectivity within psychology. Operationalizations of children’s intersubjectivity are applied to narrative vignettes used to exemplify alternative theories. This analysis demonstrates how each theorization illuminates some dimensions of interaction while excluding others. The vignettes are contrasted to show how the measurement of interactions determines the form of intersubjectivity observed. The conclusion argued for in this chapter is that although all theories depict some component of intersubjective behavior, a theory in line with the principles elaborated in the previous chapter is necessary.