The purpose of this article is to encourage research on the aspects of consumer behaviour, particularly as found in groups of consumers. For both researchers and practitioners, consumer knowledge is a critical factor in creating competitive success over time. But there is a gap in the knowledge management literature, which has recognized the importance of the customer as a source of knowledge, but has not recognized the importance of a group of consumers as well. Scholars, in fact, have not generally included a group of customers as a level of analysis. We present in this paper a conceptual representation of consumer’s group knowledge and we question about the possible role of new technologies in this representation. We have explored as much detail as possible if and how a group might be conditioned by intra - group dynamics in purchase decision making. The model’s theoretical base comes from group’s dynamics and organizational behaviour literature.