Research under the paradigm of the label feedback hypothesis has proposed a causal role for verbal labels in the online learning and processing of categories. Labeled categories are learned faster, and are subsequently more robust. The present study extends this research paradigm by considering the relationship between verbal labels and flexible categorization. Flexibility is a key trait of human cognition, and flexible categorization is important in a number of tasks. Participants learned to categorize ‘friendly’ and ‘unfriendly’ aliens either with or without names, followed by a transfer task. While selective attention to a particular dimension slowed relearning, no effect of label was found for either category learning or relearning with one exception; labels facilitated flexibility when selective attention was not involved in the transfer. The inability to replicate effects of verbal labels in category learning using similar methodologies raises interesting theoretical issues, questioning the extent to which this relationship applies.