This special issue presents original research findings aiming at contributing, at a practical level, new knowledge for both researchers and managers interested in the knowledge management and sharing within inter-firm networks. The papers here presented include contributions from worldwide: they have been selected among almost one hundred submissions and discuss empirical findings across multiple levels of analysis in a wide range of sectors. Empirical research using qualitative, quantitative or mixed methods have been welcomed. The Guest Editor has considered conceptual papers that draw on the existing literature and develop innovative contributions that improve the understanding of the topic, as well. Thus, the guest editor has been looking for a wide variety of papers that may contribute to the creation of a solid evidence base concerning knowledge management in organizations and inter-firm Networks. The research methodologies used for gathering empirical data vary from quantitative surveys to exploratory case studies based on qualitative data. Several rounds of blind peer review have been necessary and they resulted in the final form of this volume on July 2014 for publication here. All articles selected demonstrated relevance to the understanding of social software and its implications for knowledge management. Readers of this special issue should be technically savvy, scientifically demanding, and drawn to practically relevant phenomena. The special issue has been organized coherently with two "strains" of topics: the first one focused on managerial practices and operative directions of knowledge management, the other one pointed out on applications of knowledge management to inter-firm networks.