This thesis investigates progress toward design of a knowledge building community (Bereiter & Scardamalia, 1993) in a hospital setting. Knowledge building communities are those dedicated to continual improvement and progressive inquiry leading to the generation of new knowledge---they are communities of innovation (Scardamalia, 2002). Knowledge building is an epistemology aimed at improving material, social and conceptual knowledge and builds on Popper's (1972) notion of the three worlds of knowledge (Bereiter, 2002). In the present context, the goal was to foster knowledge embedded in practice---the kind of knowledge that has been the focus of work on situated cognition (Lave & Wenger, 1991; Wenger, 1998) and reflective practice (Schon, 1983, 1987). The goals of this study were threefold: (1) to shift profession specific learning and reflective practice to an interprofessional context; (2) to create dynamic opportunities for learning and reflection using real-world problems generated by health care professionals; (3) to use knowledge building epistemology to improve the tools, social practices and conceptual artifacts of use to the hospital community. Participants (N=23) included members of an interprofessional team at the Toronto Rehabilitation Institute called the Professional Practice Portfolio. An emerging methodology in the learning sciences called "design research" (Brown, 1992; Collins, 1999a; Collins, Joseph, & Bielaczyc, 2004) was used. Over an eighteen-month period, participants engaged in semi-structured and emergent activities and discourses in a second-generation computer supported intentional learning environment called Knowledge Forum RTM. Overall, results indicate that the design strategies employed succeeded at fostering interprofessional learning and reflective practice and in a workplace setting and generated new knowledge of use to the hospital community.