A new generation of Internet-based collaborative tools, commonly known as Web 2.0, has increased in popularity, availability, and power in the last few years (Kane and Fichman, 2009). Web 2.0 is a set of Internet-based applications that harness network effects by facilitating collaborative and participative computing (O'Reilly, 2006). Conceptually, Web 2.0--with its ability to combine traditional KM tools' features with social computing, where knowledge is evolved through social interactions (Parameswaran, 2007)--has been identified as an effective KM paradigm (Fitch, 2007; Mindel and Verma, 2006). With such a capability, Web 2.0 technology has the potential to address many of the KM challenges that organizations face (Minocha and Thomas, 2007; Wagner, 2006). While Web 2.0 has gained widespread popularity at the consumer level, it is still not well-understood how Web 2.0 can be effectively used for KM by enterprises. In our research, we address this critical gap in the literature by using a multiple-case research design. This dissertation examines how IT organizations use Web 2.0 technologies for Knowledge Management (KM) at the individual, project, and group level. We also investigate how the use of Web 2.0 technology for KM affects organization, group, project, and individual level outcomes. Using multiple case research design, this research provides examples of effective use of Web 2.0 for KM at the individual, project, group, and organization level. Using empirical data, this research also establishes a relationship between the uses of Web 2.0 for KM and its effects on individual, project, group, and organization levels. The extant literature has yet to examine such relationships. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://www.proquest.com/en-US/products/dissertations/individuals.shtml.]