The ability to forgo an immediate pleasure or reward in order to gain a more substantial one later.

The acquisition of the ability to delay gratification is part of a child's social and emotional development. One of the developmental differences between preschoolers and toddlers is the greater ease with which preschoolers can be persuaded to delay gratification. On the whole, however, they need adult encouragement in order to maintain this behavior. Left to their own devices, few five-year-olds will pass up something attractive even if they know they will be rewarded later on. When children this age are given the choice between a modest treat (such as a small dish of ice cream) and a more substantial one later (an ice cream sundae), few will hold out for the delayed one unless they are pressured or closely monitored by adults.

The ability to delay gratification increases markedly between the ages of 5 and 12. When kindergartners in one study were offered a choice between being given a small candy bar immediately or a larger one later, 72% chose the smaller candy bar. This number decreased to 67% among first and second graders and 49% for third and fourth graders. By the fifth and sixth grades it had fallen to 38%, nearly half the rate for kindergartners. Although all children show an improved ability to delay gratification as they get older, some are more successful at it than others.

Generally, the children who are most successful in delaying gratification in middle childhood are those with an internal locus of control (a strong belief that their actions can influence events). By contrast, children with an external locus of control are less likely to believe that it is worth exerting self-control in the present because they doubt their ability to influence events in the future.