This study reports a conceptual replication and extension of Deschamps' (1977) experiment concerning the effects of subcategorization on an existing dimension of physical classification. Using a computerized procedure and a more sophisticated statistical analysis we found support for category differentiation processes at the intra- as well as inter-class level of differentiation. In contrast to the original findings, we also found evidence for decategorization, a previously neglected potential outcome of multiple categorization procedures. Copyright © 1999 John Wiley & Sons, Ltd.