Based on ontological principles enunciated by Plato more than 2300 years ago, yet at a time when Web 3.0 technology is seen to impact the management of organizations and especially the management of organizational performance, the authors propose in this chapter to characterize the IT artefact with an approach that returns the user perspective to the forefront. As an illustration, the Performance Measurement Systems (PMS) of 16 Small and Medium-Sized Enterprises (SMEs) are investigated and characterized from their users' perspective in terms of their specific attributes as systems dedicated to managing organizational performance in the Web 3.0 era. The variety of contexts and configurations of these systems is of particular interest while looking for the principles that underlie their empirical manifestations. Results provide a framework of reference for the characterization, design, and evaluation of IT artefacts that is applicable in particular within a Web 3.0 technological context.