We examined the temporal basis of the phonological distinction between complex segments and segment sequences. Our working hypothesis was that the gestures of complex segments are coordinated with reference only to gesture onsets while segment sequences are coordinated with reference to the offset of the first gesture and the onset of the second. We evaluated this hypothesis using kinematic recordings of (1) palatalized labials,[pj], in Russian, as an example of a complex segment;(2) Russian [br] sequences; and (3) labial-glide sequences in American English:[bj],[mj],[vj],[pj]. Results indicated that Russian [br] shows sequential timing, the same pattern of coordination as all four labial-glide sequences in English; the timing of Russian [pj] was different. In line with our hypothesis, the labial and palatal gestures of Russian [pj] were coordinated by gesture onsets. Our results are consistent with distinct modes of coordination for complex segments and segment sequences (150 words).