Virtual learning environments (VLE) constitute the current information systems' (IS) category for electronically supported corporate training and development. Frequently supposed advantages of using VLE refer, for instance, to the efficiency, individuality, ubiquity, timeliness and task orientation of learning. However, a crucial precondition of realizing such advantages is an appropriate systems design. Hence, the question which specific design characteristics actually characterize successful VLE is of specific interest for training and development practice. This paper therefore addresses design characteristics by conducting an expert study that is based on a general theory of IS success and previous insights of the literature. As a result, a set of relevant, well-defined design characteristics is presented and discussed while implications for research and practice are derived.