The paper starts with a short description of Knowledge Forum (KF) (tm) and the theory it is based on. KF is the second-generation product which has started with CSILE (Computer Supported Intentional Learning Environments) at the Ontario Institute for Studies in Education. It is an asynchronous discourse medium with contributions to a community knowledge base, which resides on a server and is accessible to every user with a password. KF "permits a depth of embedding that goes well beyond what is possible with other forms of so-called knowledgeware" (Scardamalia 2002). The philosophy is to turn over to the learners the responsibility of using notes and views to create a valuable shared knowledge resource for their community and that these ideas always remain the focus of this responsibility. For Marlene Scardamalia the challenge of a knowledge building pedagogy is "to engage students in the collaborative solution of knowledge problems, in such a way that responsibility for the success of the effort is shared by the students instead of being borne by the teacher" (2002).Then the setting of two courses with university students in Hamburg/Germany and Linz/Austria is described. These two groups had to collaborate with the help of KF. After a short phase to get to know each other they had to work and learn together for 7 weeks. The task was to learn about WebQuests as a method, to work on different learning theories (6 different mixed groups with students from both universities), to use KF for communication and collaboration, and to build collaboratively their own WebQuest. Both courses ended with a presentation of results and a common reflection. Outcomes can be seen in the KF database (presented with the paper interactively), at the web-pages of the courses (http://www.ibw.uni- hamburg.de/lehre/ws0203/iblhh0203 andhttp://www.wipaed.uni-linz.ac.at/lehre/iblws0203 ), and from the questionnaire done with both groups. . In general, the results show a difference between the two groups in Hamburg and Linz concerning the use of ICT for learning purposes (those from Linz being more used to build their own web-pages and to communicate within courses regularly vie email). The students in Linz perceived KF easier to handle. They learned rather fast to work with KF in a useful manner, and they were rather satisfied with KF in an English-only version. Both groups used KF strongly for communication. Cooperation amongst the groups was experienced more difficult. Within the local small groups and within the whole local group cooperation by using KF could have been better. Collaborative learning did not take place as much as intended. Learning from each other was only successful in some areas. There was a significant difference between Hamburg and Linz: the students from Hamburg seemed to have learned more from each other than the students from Linz. This emphasizes another general outcome: learning in a collaborative way is not really appreciated. Both groups rather agreed than disagreed to the statement that they would prefer individual learning to collaborative learning. Anyway, students from Linz seemed to be more used to collaborative working and learning than those from Hamburg. Learning with the PC was no problem at all for both groups. Eventually, KF was rated helpful for knowledge building processes; however, it should be accompanied by additional software or tools (esp. by email). Both groups disagreed to the statements that KF is helpful for self-directed learning or for taking more responsibility for their learning success. The picture that is drawn by the answers is somewhat conflictive. There seems to be a tension between the wish to learn individually and the feeling that collaborative learning can have more positive outcomes.