Purpose: The material extrusion (ME) process induces variations in the final part¿s microscopic and macroscopic structural characteristics. This viewpoint article aims to uncover the relation between ME fabrication parameters and the microstructural and mesostructural characteristics of the ME BASF Ultrafuse Steel 316L metal parts. These characteristics can affect the structural integrity of the produced parts and components used in various engineering applications. Design/methodology/approach: Recent studies on the ME BASF Ultrafuse Steel 316L are reviewed, with a focus on those which report microstructural and mesostructural characteristics that may affect structural integrity. Findings: A relationship between ME fabrication parameters and subsequent microstructural and mesostructural characteristics is discussed. Common microstructural and mesostructural/macrostructural defects are also highlighted and discussed. Originality/value: This viewpoint article attempts to bridge the existing gap in the literature, highlighting the influence of ME fabrication parameters on Steel 316L parts fabricated via this additive manufacturing method. Moreover, this article identifies and discusses important considerations for the purposes of selecting and optimising the structural integrity of ME-fabricated Steel 316L parts.