Knowledge-based communities are important but poorly understood systems for helping enterprises maintain their organizational integrity and address organizational imperatives. Based on an autopoietic theory of organization, we examine the emergence and development of knowledge-based communities at different scales up to large distributed enterprises and industry clusters. Knowledge-based communities are highly complex systems that evolve and mature through the phased emergence of new features and capabilities. Development and support of successfully sustainable communities needs to be based on a better understanding of how these features and capabilities emerge. To comprehend the impact of emergent behavior within and beyond organizational communities requires an understanding of the social or sociological aspects of a system in relation to the explicit formal/physical structures in the organization.