This study investigates timing of communicative behaviour with respect to speaker's respiratory cycle. The data is drawn from a corpus of multiparty conversations in Swedish. We find that while longer utterances (> 1 s) are tied, predictably, primarily to exhalation onset, shorter vocalisations are spread more uniformly across the respiratory cycle. In addition, nods, which are free from any respiratory constraints, are most frequently found around exhalation offsets, where respiratory requirements for even a short utterance are not satisfied. We interpret the results to reflect the economy principle in speech production, whereby respiratory effort, associated primarily with starting a new respiratory cycle, is minimised within the scope of speaker's communicative goals.