The discussion about corporate sustainability performance already has a rich and longstanding history.Todate corporate sustainability performance is a key issue in many companies. However, when asked what it means or how to apply this construct in a concrete business context, many entrepreneurs and managers are not able to give an answer. This confusion may be due to the multitude of definitions and descriptions of corporate sustainability performance constructs.To get a better understanding of corporate sustainability performance and to help companies shape their corporate sustainability performance, a plenitude of (reporting) guidelines are available today. However, because of a rich variation in foci, these guidelines also contribute to the corporate sustainability performance confusion among business people.Companies are no longer solely judged on the financial performance, but they also have to account for their sustainability performance to a variety of stakeholders. However, along with the increasing attention of stakeholders for corporate sustainability performance, the number of organizations that assessing companies’ governance, social, ecological and economic performance also increasesThe aim of this paper is to research the validity and compatibility of the screening instruments of two widely respected sustainability rating agencies: the Zurich (Switzerland) based Sustainable Asset Management Group (SAM) and the Boston (USA) based KLD analytics, Inc (KLD). These screening instruments are benchmarked against the Corporate Sustainability Analysis Framework designed and developed by Dommerholt 2009. The results suggest that the SAM and KLD instruments are imperfect measures of corporate sustainability performance, implying that the validity of these measures is questionable. The results also show that the screening instruments are not really compatible indicating that these instruments cannot be used interchangeably because of differences in the underlying conceptions of corporate sustainability performance. Therefore we can say that these screening instruments too seem to add to the confusions surrounding corporate sustainability performance (measurement).