Designer support is critical for facilitating collaboration and knowledge construction in an online learning environment. Designer support in this paper refers to the mechanisms that a designer builds in a technology-mediated environment to facilitate online learning. This paper focuses on two aspects of designer support: 1) creating a shared context, and 2) facilitating online communication and knowledge construction. Examples of these two aspects of support are presented along a continuum ranging from technology that simply allows collaboration to collaborative technology that makes collaboration more accessible to users. Examples of strategies for creating a shared context include the use of metaphorical designs to graphically represent the virtual environment for intuitive navigation and role transplantation, the use of informational support for decision-making, and the use of multiple information channels and tools to support coordinated collaboration in task-based projects. In order to facilitate online communication and knowledge construction, on the other hand, designers can employ communication scaffolds to structure online communication and artifacts as shared representations that provide contexts for online discussions. Finally, the potential application of similar mechanisms to online course management systems is discussed. (Contains 6 figures.)