The distinction among groups within the “SME” category assumes that the enterprises forming these groups have a certain number of common characterizing features.From this perspective and within the framework of this study, we investigate the following issue : within the group of medium-sized businesses, can we iden-tify homogenous types of behaviour in the marketing approach, or do we rather encounter differentiated types of behaviour ? In this paper, we answer that question in relation to two major variables, i.e. the respective influence of enterprise size and profile on observed marketing practices. With respect to size, a minor level of influence can be seen in the informational approach of medium-sized enterprises. In this area, differentiated types of behaviour can be observed, particularly with respect to the level of attention devoted to competitors. The larger firms in this category have a more articulated informational approach than their smaller counterparts. Since this finding is related to the impact of enterprise profile on observed behaviours, this feature clearly differentiates among sub-groups of medium-sized enterprises.