Summary In this report we try to get a deeper insight into what we can theoretically expect, what we already know from research, and what we can also measure empirically, about the effects of employee participation at the organisational level in Belgium . We focus on representative participation, i.e. participation via trade union-based participation structures. This report is based on an overview of recent research findings, as well as testing expectations from this research literature for Belgium based on recently collected survey data. The review of the literature shows that for various outcomes there are conflicting conclusions, that the existing research is remarkably scarce for Belgium, but also that there are a number of confirmed and expected effects that we can test for the Belgian context. When we empirically test this on the basis of the survey data, we learn from a large scale HIVA - KU Leuven employee survey (N = 3.527, 2019) that the presence of trade union representatives has a positive effect ... : Please cite this report as: Hermans M., Desiere S. & Lenaerts, K. (2020). Maakt de vakbond het verschil? Effecten van werknemersvertegenwoordiging op organisatieniveau. Leuven: HIVA – KU Leuven. https://doi.org/10.5281/zenodo.4139718. ...