This article focuses on facilitating learners' collaborative knowledge construction in case-based learning scenarios. The article first describes how case-based learning can promote knowledge acquisition and then discusses the characteristics of videoconferencing in such scenarios. Then we focus our attention on the process and outcomes of the collaborative case solution. Following this, we concentrate on the issue of instructional support and present two methods which could particularly facilitate learners in their collaborative case-solving: collaboration scripts and content schemes. The empirical section describes an experimental study with 150 participants who collaborated in groups of three via videoconferencing. These triads were assigned randomly to one of four conditions, which involved using a collaboration script and a content scheme. Results reveal that the collaboration script reduced the level of learners' content-specific negotiation and the content scheme reduced the level of strategic negotiation. The content scheme significantly improved the collaborative case solution. Furthermore, learners' strategic negotiation also had a positive association with the collaborative case solution. (Contains 3 figures, 4 footnotes and 7 tables.)