Advancements in mobile technologies leverage the potential of m-business to impact organizational performance. This study aims at identifying the determinants of m-business usage and its impact on the firm?s performance. The Technology-Organization-Environment (TOE), Diffusion of Innovation (DOI) and Resource-Based View (RBV) theories ground this research?s conceptual model for assessing the value of m-business in an organizational context. Two different methodologies are combined in this study. The first consists on an exploratory study based on expert interviews to define m-business value and the impacts that its usage may have on the organization. The second develops a nomological net to assess m-business usage and value. The measurement and structural models are then tested using structural equation modelling as implemented in Smart PLS based on the data of 180 Portuguese organizations. Results show that compatibility and complexity are not among the factors that are antecedents of m-business usage, while relative advantages, technology competence, technology integration, managerial obstacles, competitive pressure, low partner pressure and mobile environment are significant antecedents of m-business usage. Additionally, supporting the results from the interviews, impacts on the procurement dimension is less significant than impacts on the marketing and sales and internal operations dimensions of m-business value.