During conversation, interlocutors build on the set of shared beliefs known as common ground. Although there is general agreement that interlocutors maintain representations of common ground, there is no consensus regarding whether common-ground representations constrain initial language interpretation processes. Here, I propose that executive functioning--specifically, failures in inhibition control--can account for some occasional insensitivities to common-ground information. The present article presents the results of an experiment that demonstrates that individual differences in inhibition control determine the degree to which addressees successfully inhibit perspective-inappropriate interpretations of temporary referential ambiguities in their partner's speech. Whether mentioned information was grounded or not also played a role, suggesting that addressees may show sensitivity to common ground only when it is established collaboratively. The results suggest that, in conversation, perspective information routinely guides online language processing and that occasional insensitivities to perspective can be attributed partly to difficulties in inhibiting perspective-inappropriate interpretations.