Manufacturing Execution Systems (MES) are at the heart of industrial organizations’ endeavors. While MES were traditionally positioned as an integration technology to bridge the shop-floor with higher level business systems, their current focus seems to be on the digitization of shop-floor activities for the collection, analysis and exchange of real-time information. Still, there remains dispute on the role of MES, specifically with respect to the functions they support in relation to other information systems in the automation pyramid, and their resulting interactions with humans. While MES are often positioned as the top layer of automated control of manufacturing processes, it is perceived by others as an integrated decision support system for the shop-floor. This study aims to shed light on the role of MES to either automate or to augment human tasks. Based on insights of a case study, we found that MES are neither automatic control nor solely decision support. MES’ main role is the creation and maintenance of digital twins of products. This involves human interaction, which closely resembles work related to computer-aided engineering (CAE) systems. We expect that work in the sphere of MES will therefore increasingly resemble engineering work.