Web-based processes of learning and collaboration produce an enlarged structural opportunity at many levels. Careful structuring of the virtual space supports and adds quality to both collaborative learning between students, and to instruction. Such enhancement in quality may take place through use of individual and collaborative spaces for learning activities, overview of process and content, increased clarity of learning expectations, and facilitation of collaborative and individual processes of reflection and self-reflection. This chapter investigates the structuring potential of a virtual version of portfolios for supporting these aspects. It discusses the conceptual and structural complexity associated with design and use of virtual portfolios from the perspective of, both learners and instructors, and on the basis of the design and use of virtual portfolios in a web-based American course on global change.