In the past two decades, the related concepts of regional innovation systems and clusters have become widely circulated in both academic and policy circles. Both concepts depart from the idea that innovations predominantly occur as a result of interactions between various actors, rather than as a result of a solitary genius (Håkansson, 1987; von Hippel; 1988; Lundvall, 1992), and that innovation and industrial transformation result from interactions across sets of actors within a spatially defined territory (e.g., countries, regions). Researchers within this field posit that most innovations are based on some form of problem solving in which someone generally perceives a problem and turns to someone else for help and advice (Teigland, Lindqvist, Malmberg & Waxell, 2004), and that spatial proximity seems to enhance the processes of interactive learning and innovation (Malmberg & Maskell, 2002). These assumptions draw striking parallels to the traditional concept of communities of practice (Brown & Duguid, 1991; Orr, 1990; Wenger, 1998), which are emergent groups of people who know each other relatively intimately and who primarily work together directly in face-to-face situations since learning and knowledge are situated within a physical setting (Teigland, 2003). Thus, the purpose of this short article is to provide a brief discussion of clusters and regional innovation systems, and propose broad areas of future research in which the community of practice concept can contribute to our understanding of clusters and regional innovation systems.