This literature review examines a hypermedia learning environment from a semantic network basis and the application of such an environment to second language learning. (A semantic network is defined as a conceptual representation of knowledge in human memory). The discussion is organized under the following headings and subheadings: (1) Advantages and Limitations of Hypermedia--nonlinearness, associativity, flexibility, efficiency, disorientation, cognitive overhead, and learner control; (2) Theoretical Assumptions of a Semantic-Network-Based Hypermedia Learning Environment--John Dewey's philosophy, Norman's Mental Model Theory, Craik and Lockhart's Levels of Processing Theory, and Rumelhart and Norman's Modes of Learning Theory; (3) Hypermedia and Semantic Networks; and (4) Semantic-Network-Based Learning Environment and Second Language Learning--Communicative Computer Assisted Language Learning (CALL) and Communicative CALL and Hypermedia Assisted Instruction. It is concluded that a semantic-network-based hypermedia learning environment, grounded in levels of processing theory and modes of learning theory, seems to be particularly appropriate for second language learning, as it provides not only a vivid and natural environment for the accumulation of the facts of a second/foreign language, but also tools to synthesize and integrate the new knowledge, and reconstruct the existing knowledge. Two tables and three figures are included. (Contains 38 references.) (ALF)