In order to achieve climate protection targets and curb the destruction of nature, a sustainable use of resources is required, which is to be achieved through the efficient use of energy, raw materials and water, among other things. Increased efficiency in production and services means that fewer resources are required. However, this is often accompanied by cost savings, which influence the consumer behaviour of users and lead to an increase in demand. In this way, efficiency gains, which are expressed in a reduction in the use of resources, are partially offset. The so-called rebound effect expresses the difference between the resource savings possible through increased efficiency and the actual savings. Direct rebound effects occur when more products or services of the same type are consumed. If the cost savings are used to utilise other products or services, these are referred to as indirect rebound effects. Rebound effects can account for up to 100 % of the savings achieved by increasing efficiency. Overcompensation that occurs when more resources or energy consumption are recorded as a result of the effect is known as a backfire. Efficiency policy then leads to the opposite effect and increases resource consumption. The aim of this module is to make it clear that measures to increase efficiency alone will not solve the problem of environmental degradation and climate change.