This lever is about increasing or decreasing real or perceived costs and benefits, in the broadest sense (that is, what we give up or gain for a given choice, e.g., money, time, or effort). In more theoretical terms, the use of material or financial incentives comes from early economic and rational actor theories such as utility maximization about how people make choices and develop preferences to further their interests. Specifically, these models tell us that most of our preferences are guided by the real (or perceived) value of our choices, and so changes to this would in turn lead to changes in behavior. In reality, preferences rely on much more than material incentives alone, but the attractiveness of a choice relative to others plays an important part in our decision-making. Choices are typically more attractive if they come at lower costs (e.g. lower price, or less effort) and with greater benefits . Material incentives were some of the first strategies recommended for behavior change, and while the “economic case” for a decision continues to be relevant, in many contexts this will not be sufficient to induce large-scale behavior change.