In recent decades, Israel’s growing population and rising incomes have seen consumption increase substantially, bringing with it considerable pressure on the environment. One of the main environmental pressures is from the ever-increasing transport activity, especially the use of private vehicles. Although travelling in a private vehicle brings benefits to the individual using it, this entails costs to society as a whole. These social costs extend beyond the private costs of the car and the fuel borne by the car user, imposing a burden on public health and the environment. Transport involves noise, local air pollution, and contributes to climate change, congestion, accidents, and wear and tear to infrastructure. All these negatively affect public health and quality of life in general, a fact not taken into account when an individual chooses whether or not to buy a car. This is known as a “market failure”, because the price of a car does not fully reflect the social costs of using it. Governments can correct market failures like these through policies that ensure that the actual costs to society are incorporated within the price of a car, thus influencing consumers’ purchases. This paper describes how Israel developed an innovative scheme to encourage consumers to choose less polluting cars. The Green Tax scheme targets reductions in all polluting vehicle emissions, not only carbon dioxide (CO2). The paper outlines the design process, reflects on the challenges encountered and the environmental, economic and social impacts. It concludes by discussing the wider lessons that are raised for other governments seeking to tackle similar environmental problems.