Front-of-package and on-shelf nutrition labeling systems in supermarkets have been shown to lead to only modest increases in the purchase of more nutritious foods. Educational campaigns may increase the use of these types of product labels if (1) there is a lack of consumer awareness and/or understanding of the labels, and (2) the information provided leads consumers to prefer different products. The authors study a large-scale national campaign for the Guiding Stars nutrition labels conducted by a grocery retailer in Canada that implemented the labels. Using detailed household transaction data, the authors find only a small increase in the purchase of higher star–rated foods during the campaign, driven by produce purchases, and 60% of the effect disappears after the campaign’s conclusion. Exit surveys were conducted outside of stores before and after the campaign to explain the limited response. Awareness and understanding of the nutrition labeling system increased marginally after the campaign, but there was no increase in self-reported use.