The paper investigates the role of Information and Communication Technologies (ICT) and specifically of the web 2.0 in supporting knowledge management (KM) processes. A literature review analyses how the web 2.0 transforms the implementation of KM by supporting conversational and collaborative KM processes that in turn divert KM from a technology-centric to a people-centric approach. The discussion also reveals how different ways of exploiting web 2.0 reflect different levels of technology supported KM practices. The study also investigated the type and the level of web 2.0 exploitation for KM purposes in the Greek tourism industry by collecting empirical data from tourism professionals. The data was analysed by performing an utilisation-importance analysis that compared data measuring the actual utilisation of web 2.0 with the perceived utilisation importance of web 2.0 for KM purposes. The analysis identified several gaps and opportunities in relation to web 2.0 exploitation for KM purposes. The paper concludes by providing practical and theoretical implications for enhancing the exploitation of web 2.0 for KM purposes.