This study investigates the variability in the temporal alignment of turn initiations and its relationship to the entrainment and power structure between the interlocutors. The data come from spontaneous, task-oriented human-human dialogues in Standard American English, and focus on singleword turn-initial utterances. The descriptive and quantitative analysis of the data show that an emergent asymmetrical dominance relationship is constructed partly through the accommodation (or its absence) to the temporal and rhythmic features of interlocutors' turn-initiations.