I investigated the impact of economic and non-monetary instruments on sustainable grocery consumption. I tested whether these instruments reduce carbon footprint of shopping baskets and increase CO2 knowledge in an experimental online grocery shop. In the first empirical chapter, I disentangled the price effect and psychological impact of carbon tax by testing the effect of price adjustments, injunctive norms, and tax salience on basket CO2. In the second experiment, the impact of traffic lights carbon labels were also tested. Over two experiments, little or no impact of carbon tax on consumption was found. However, I found that carbon labels decreased basket CO2. While tax signposts did not improve knowledge, carbon labels and norms did. In the second empirical chapter, I decomposed the psychological and price effect of bonus-malus tax by testing the effect of price adjustments, tax salience, and tax justification messages on basket CO2. In the second experiment, I tested whether carbon labels had an impact on basket CO2 and knowledge. Over two experiments, no effect of bonus-malus on basket CO2 was found. However, carbon labels decreased basket CO2 and improved knowledge. I found evidence for the impact of tax signposts on knowledge. Additionally, in these first two empirical chapters, it was found that knowledge was a mediator of the relationship between labels and consumption. In the third empirical chapter, I investigated the impact of goal setting techniques and of the provision of carbon footprint information about the products and the basket on consumption and compared their effectiveness. Over three experiments, it was found that goal-setting techniques were effective in reducing basket CO2. Multiple visits ameliorated knowledge, in the goal setting condition, even though it did not decrease basket CO2. While colour coded labels, on their own, did not have an impact on basket CO2, numerical labels did, after combing the data of two experiments.