We discuss a microscopic model-based setting that allows one to readily access the large-distance asymptotic behaviour of multi-point correlation functions. This setting relies on a limited number of hypotheses about the model's spectrum and form-factor expectation values of local operators between eigenvectors of the model'sHamiltonian. In particular, it holds for several one-dimensional quantum integrable models. However, in principle, it is much more general and thus applicable as well to non-integrable models. This is joint work with N. Kitanine, J.-M. Maillet and V. Terras.