We present a unique empirical analysis of the properties of the New Keynesian Phillips Curve (NKPC) using an international data set of aggregate and disaggregate sectoral inflation. Our results from panel time‐series estimation clearly indicate that sectoral heterogeneity has important consequences for aggregate inflation behavior. Heterogeneity helps to explain the overestimation of inflation persistence and underestimation of the role of marginal costs in empirical investigations of the NKPC that use aggregate data. We find that combining disaggregate information with heterogeneous‐consistent estimation techniques helps to reconcile, to a large extent, the NKPC with the data.