Over the past few decades, the practice of education and training has been shifting from traditional knowledge transmission approaches to constructivist approaches of knowledge construction. This evolution is supported by research in cognitive science, education, and discourse processes. Constructivist theories of learning assume that students use their prior knowledge to construct new knowledge that is relevant to their individual experiences and the texts that they read. There also is a widespread belief that knowledge construction is facilitated by technology and multiple channels of communication. Given the enormous increase of networked multi-channeled technologies, researchers have been exploring how people construct knowledge in an interactive environment. The aim of this special issue is to identify some models of the cognitive discourse and linguistic processes that underlie knowledge construction and to analyze how such processes are supported in technologies with diverse channels of communication. (Contains 1 figure.)