Temporal distribution of individual price changes is of crucial importance for business cycle theory and for the microfoundations of price adjustment. While it is routinely assumed that price changes are staggered over time, both theory and evidence are ambiguous. We use a large Belgian data set to analyze whether price changes are staggered or synchronized. We find that the more aggregated are the data, the closer is the distribution to perfect staggering. The results hold both for aggregation across products, and across locations. They are consistent with an economy in which idiosyncratic shocks are the main cause of price changes. (JEL E30, E31, D40)