Recent developments in measurement theory for QFT offer a new ‘diagnostic’ of which conditions are necessary or sufficient for blocking superluminal signalling and superluminal causal influences. We will argue that Microcausality is not sufficient for no-signalling and we will examine dynamical assumptions that ensure ‘dynamical locality’ for QFT and its associated measurement theory. For concrete models that represent the measurement process as a local scattering process, we will analyse the role of causal factorization conditions and their relation to Microcausality. Finally, we will argue that this reformulation of measurement theory for QFT such that it respects relativistic causality has consequences for the space of possible interpretations of the theory and for the Measurement Problem.