Yeast cells growing under continuous conditions at high cellular density employ a robust metabolic cycle for energy generation in which a respiratory burst alternates with a non-respiratory, reductive phase. Two related studies have recently shown that global transcriptional co-regulation of genes defines the phases of this metabolic network in time and synchronizes cell division with metabolism. The finding that many fundamental and diverse cellular processes can be coordinated by global mRNA oscillations implies the existence of a more widespread metabolic clock that might also be present in higher eukaryotes.