Abstract: “One among the major concerns of managers since the emergence of Information Technology (IT) in organizations in the sixties is to prove that the IT /IS (information system) investments have a positive impact on the organization. Over time, the IS’s evaluation dominated the research in IS field. Several variables of IS measurement, called IS success measurements, like user satisfaction, system use, organizational performance and u ser decisional performance [41 ] were developed and considered as substitute for the effectiveness of IS (IS e ffectiveness is measured against the achievement of objectives according to Hamilton and Chervany [ 25 ]). User satisfaction is the most use d in measuring the success of IS and their impact on the organization. This article focuses on the "user satisfaction". Through the analysis of a set of selected articles from the literature about the evaluation of IS , w e have developed a class model (using UML formalism) about the construct user satisfaction.”

Keywords: IS evaluation, user satisfaction, modelization of user satisfaction.