Recent literature reviews have highlighted the need to better understand the relation between speaker and listener behavior when teaching learners with autism spectrum disorders (ASD). The current study used a modified parallel-treatments design to compare directly the degree to which tact and listener behavior emerged during instruction in the opposite relation for 4 children with ASD. Results showed tact training to be either equally or more efficient than listener training for all participants. However, varied patterns of emergent responding across participants indicate a need for further research. Data on collateral responding during instruction did not suggest that the presence or absence of overt collateral behaviors were predictive of emergence. The results highlight the importance for clinicians and educators to assess emergent tact and listener repertoires periodically.