Gambling involves wagering something of value (money, property, etc.) on a random event with the intent of winning something else of value (e.g., money or other goods). In some instances, strategy is discounted. Examples include betting on sports events like football games, horse races, or scratchcards; placing bets in a bar, casino, or private setting; and playing card games for entertainment or social interaction.

Gambling has both positive and negative impacts on the economy and society. In some cases, it stimulates job creation and wage increases, tax revenues, consumer benefits, and economic growth; in other cases it can exacerbate inequality, create financial problems, and cause social issues such as homelessness and unemployment. It can also lead to domestic and interpersonal harm, such as family violence and petty theft.

Behavioral researchers have faced methodological challenges when studying gambling and happiness. One issue has been the difficulty of measuring non-monetary impacts that are often ignored in calculations. For instance, Williams et al. defined social costs as those that aggregate societal real wealth and benefit no one; whereas, community/society level benefits are those that improve the quality of life and the wellbeing of the people in the community. Other challenges include the lack of a common methodology for calculating the externalities of gambling at the personal, interpersonal, and community/society levels. This is important because these impacts can be long-term and affect multiple people, including families. They can also be invisible and hard to measure.