In big companies, Circular Economy (CE) is being explored, nevertheless, Small and Medium-sized Enterprises (SMEs) struggle to follow because of particular barriers and a lack of practical guide. Here, we use Style & Design, a French industrial SME, as a case study to explore how SMEs can perform a successful CE integration. This article aims at proposing a multi-internal actor circularity diagnosis method. It focuses on building an inclusive and co-constructed therefore well-accepted and persistent integration of CE for SMEs, which is lacking today in the existing literature. This work relies on a mixed qualitative and quantitative data analysis applied on a corpus of 42 one-hour-long semi-structured interviews, with 37 different professions. We capture the view of the current and desired situation and identify CE barriers unique to each interviewed worker. We also connect with each worker and open the dialog for the rest of the CE deployment. The final goal is to assemble this worker-oriented diagnosis with quantitative diagnosis, like Life Cycle Analysis of the products and Material Flow Analysis of the factory, to diagnose a complete picture of an industrial SME circularity.