The Web is now used by many companies worldwide in order to meet their training needs. The usage of the web as an instructional tool is expected to be extended even more in the near future. Recent discussions on the use of web as a training tool tend to focus on technical features of the Web while not much attention is paid to pedagogical features of WBT. The purpose of this article is to delineate general design principles from existing literature and empirical research results in order to provide a pedagogical framework for WBT designers to develop effective Web-Based Training programs. For the investigation purposes, previous research results and discussion ideas in the literature were categorized into four broad areas: 1) ideas from distance education tradition, 2) ideas from constructivist learning environment design, 3) instructional design ideas from changed instructor-learner roles, and 4) ideas on the practical design considerations in adopting various technological features of the Web. Where appropriate, conceptual frameworks from existing theories such as the Transactional Distance Theory and Constructivist approach were adopted for examining WBT design issues and principles. Some of the major results of the paper include that: 1. in designing web structure, flexibility needs to be ensured. The flexibility can be achieved by adopting content expandability and content adaptability. 2. in designing dialogue between and/or within instructors and learners, a variety of communication channels needs to be established. That is, the multiple channels of dialogue need to be provided to ensure student participation and satisfaction. 3. in WBT, it is important to allow participant\'s autonomy and to provide cooperative learning environment. 4. constructivist learning environment design is especially useful for problem solving and cooperative learning. The paper concludes that improvement-oriented research rather than conclusion- oriented research is recommended for the future research on this area. Key words: Web-Based Training, design principles, Transactional Distance Theory, constructivist learning environment