The Operator Product Expansion (OPE) is a theoretical tool for studying the short distance behaviour of products of quantum fields, which has found practical uses both in explicit calculations as well as in conceptual studies in quantum field theory. I will review new insights into the status and properties of the OPE within Euclidean perturbation theory, addressing in particular the topics of convergence and “factorisation” of the expansion. Further, I will present a novel recursive scheme for the perturbative computation of OPE coefficients, based solely on the zeroth order coefficients as initial input. These results are derived within the renormalisation group flow equation approach to perturbative quantum field theory, which I will also briefly review.

CPHT X