Reducing the number of hours worked is one of the most effective strategies to lower our carbon footprint, as it means using less machinery and reducing commuting, both of which cut emissions. Additionally, a four-day work week should lead to reduced consumption. When people work long hours, they tend to consume more. To encourage people to engage in sustainable activities like cooking food at home, biking and making eco-friendly home improvements, they need more time. Research on French families’ work and consumption patterns confirms that, to be more sustainable, families need to work less. Many countries around the world have experimented with and implemented shorter work weeks with remarkable success. In Iceland, a large-scale trial of a four-day work week with no reduction in pay led to increased productivity, improved employee well-being and reduced stress levels.