Altruism refers to any behavior that is designed to increase another person’s welfare, and particularly those actions that do not seem to provide a direct reward to the person who performs them. Every day numerous acts of altruism occur all around us. People give up substantial time and energy to help others.

The tendency to help others is at least in part a basic feature of human nature, designed to help us help ourselves. Altruism enhances our reproductive success by helping the species as a whole survive and prosper. We are particularly helpful to our kin and to people we perceive as being similar to us. We also help people who are not related or similar as the result of reciprocal altruism. By cooperating with others, we increase our and others’ chances of survival and reproductive success.

We are more likely to help when we are rewarded and less likely when the perceived costs of helping are high. When we act altruistically, we may gain a reputation as a person with high status who is able and willing to help others. Some countries have enacted Good Samaritan laws that require people to provide or call for aid in an emergency if they can do so. We also learn to help by modeling the helpful behavior of others.

Social norms for helping include the reciprocity norm, which reminds us that we should follow the principles of reciprocal altruism, and the social responsibility norm, which tells us that we should try to help others who need assistance, even without any expectation of future payback.

We react to people in large part on the basis of how they make us feel and how we think we will feel if we help them. Positive mood states increase helping, and negative affective states, particularly guilt, do also. Personal distress refers to the negative feelings and emotions that we may experience when we view another person’s distress. Empathy refers to an affective response in which a person understands, and even feels, another person’s emotional distress and when he or she experiences events the way the other person does.

Latané and Darley’s decision model of bystander intervention has represented an important theoretical framework for helping us understand the role of situational variables on helping. According to the model, whether or not we help depends on the outcomes of a series of decisions that involve noticing the event, interpreting the situation as one requiring assistance, deciding to take personal responsibility, and implementing action.

Some people—for instance, those with altruistic personalities—are more helpful than others. And we help some people more than we help others; our perception of the amount of the need is important. We tend to provide less help to people who seem to have brought on their own problems or who don’t seem to be working very hard to solve them on their own. Gender differences in helping depend on the type of helping that is required. Men are more likely to help in situations that involve physical strength, whereas women are more likely than men to help in situations that involve long-term nurturance and caring, particularly within close relationships.

In some cases, helping can create negative consequences. Dependency-oriented help may make the helped feel negative emotions, such as embarrassment and worry that they are seen as incompetent or dependent. Autonomy-oriented help is more easily accepted and will be more beneficial in the long run.

Norms about helping vary across cultures, for instance, between Eastern and Western cultures. The strong individualistic norms in cultures such as the United States make it seem inappropriate to help in cases where we do not have a personal interest. People may feel more comfortable helping when they feel that they are acting, at least in part, in their own self-interest.

We can increase helping by using our theoretical knowledge about the factors that produce it. Our strategies can be based on using both self- concern and other-concern. In terms of self-concern, if helping is seen as something positive for the self, people will help more. In terms of other-concern, we may try to increase our social connections with others, thereby increasing the likelihood we will help them. We must work to instill the appropriate norms about helping in our children. In emergency situations, we must be must be sure to disambiguate the emergency to others rather than assuming that those others will notice and interpret the event as one requiring help, and to help individuals experience that they have a personal responsibility to intervene.

In sum, altruism is an important and frequent part of human lives. We couldn’t live without the help we receive from others, and we are generally willing in many cases to return that help. Helping others is beneficial to them, but helping is also beneficial to us—we often enjoy being helpful, and helping can make us feel good and be healthy.