The new globalized and demanding business environment of the 21st century has created a shift from traditional organizations to more loose and flexible business schemes shaped in the form of Virtual Enterprises. This transformation would never have been successful without the support of Information Technologies and particularly the Web. Internet, in the last decade, has become the universal medium of interactions between distributed entities. In this chapter, the issue of Knowledge Management support for Virtual Enterprises is discussed. Building upon the current state of the art, this chapter aims to identify the major knowledge requirements of VEs, in an effort to provide a roadmap towards a holistic Knowledge Management framework that will satisfy the excessive knowledge needs of Virtual Enterprises at the interorganizational level. In that context, the role of supporting Web and Semantic Web technologies for the enactment of KM in VEs is described in detail.