This paper deals with computer support for collaborative learning environments. Our analysis is based on a moderate constructivist view on learning, which emphasizes the need to support learners instructionally in their collaborative knowledge construction. We will first illustrate the extent to which the computer can provide tools for supporting collaborative knowledge construction. Secondly, we will focus on instruction itself and show the kinds of advanced instructional methods that computer tools may provide for the learners. Furthermore, we will discuss the learners’ (...) prerequisites and how they must be considered when constructing learning environments. (shrink)