interpersonal attraction

Mere exposure (including the propinquity effect)

Mere exposure is the tendency to develop greater liking for something or someone simply through repeated exposure. The propinquity effect is the related finding that physical or functional closeness increases the likelihood of interaction and friendship. Familiarity can make people seem more comfortable and likable.

Similarity vs. complementarity

People are generally more attracted to others who share their attitudes, interests, values, and backgrounds. This is the similarity-attraction effect. Complementarity is the idea that people are attracted to others whose traits or needs differ in ways that fit together; however, research generally provides stronger support for similarity than for the claim that opposites attract.

Physical attractiveness

Physical appearance can influence first impressions and social treatment. Attractive people are often assumed to have other positive qualities, a bias called the 'what is beautiful is good' stereotype. Attractiveness can affect evaluations, but it does not reliably indicate a person's personality, ability, or character.

Social exchange theory

The theory that people evaluate relationships in terms of rewards and costs. Rewards include benefits such as affection, support, and companionship; costs include effort, conflict, and sacrifices. People tend to be more satisfied when the rewards they experience compare favorably with their expectations and alternatives.

Comparison level

A person's standard for what they believe they should receive in a relationship, based on expectations and past experiences. If the relationship's rewards seem to exceed this standard, the person is more likely to feel satisfied; if they fall below it, dissatisfaction is more likely.

Comparison level for alternatives

A person's estimate of how good their relationship would be compared with the options available outside it, including being single or having another partner. It helps predict whether someone feels they would be better off staying or leaving. It is distinct from satisfaction: someone can be satisfied but still see attractive alternatives.

Equity theory

The idea that people are most satisfied when the ratio of their contributions and outcomes is fair compared with their partner's ratio. Contributions may include time, effort, or support; outcomes may include affection, help, or benefits. Fairness—not necessarily identical contributions—is central.

Exchange vs. communal relationships

Exchange relationships are guided by expectations of repayment and fairness: people keep track of benefits and return favors. Communal relationships are guided by concern for the other person's needs, with help given because the person needs it rather than because repayment is expected. Friendships and close romantic relationships are often more communal.

Gender differences: evolutionary psychology

An evolutionary explanation argues that some average differences in mate preferences may reflect different historical reproductive costs and parental investment. For example, the theory predicts that men may place relatively greater emphasis on cues to fertility, while women may place relatively greater emphasis on resources and status. These are proposed average tendencies, not rules for every person, and the explanation is debated.

Gender differences: social role/power explanations

A social-role explanation argues that gender differences in mate preferences can reflect unequal social power, economic opportunities, and culturally learned expectations rather than fixed biological differences. For example, when women have less access to resources and power, financial security in a partner may become more important; greater gender equality may reduce some observed differences.

Attachment styles

Attachment theory proposes that early experiences with caregivers can shape expectations and behavior in close relationships. Secure attachment involves comfort with closeness and trust. Avoidant attachment involves discomfort with dependence or intimacy. Anxious/ambivalent attachment involves worry about rejection and a strong desire for closeness. Disorganized attachment involves inconsistent, conflicted approach-and-avoidance behavior.

Companionate vs. passionate love

Passionate love is an intense state of longing, excitement, and strong physical or emotional arousal for another person. Companionate love is a deep, affectionate bond involving intimacy, trust, attachment, and commitment. Long-term relationships may shift from intense passion toward companionate love, although both can coexist.

Investment model of commitment

The investment model proposes that commitment is influenced by relationship satisfaction, the quality of alternatives, and investments. People tend to be more committed when they are satisfied, perceive alternatives as less appealing, and have invested more—such as time, shared experiences, money, or children—in the relationship.

Communication in relationships

Communication patterns help distinguish healthier relationships from distressed ones. Constructive communication includes listening, expressing needs clearly, and discussing disagreements without escalating hostility. Destructive patterns include negative affect reciprocity, demand/withdraw cycles, and interpretations that assume a partner's negative behavior reflects permanent or intentional flaws.

Negative affect reciprocity

A cycle in which one partner's negative emotion or behavior leads the other partner to respond negatively, which then triggers more negativity. The interaction escalates instead of resolving the disagreement.

Demand/withdraw pattern

A communication pattern in which one partner pressures, criticizes, or repeatedly demands change while the other avoids the discussion, shuts down, or withdraws. Each person's response can intensify the other's behavior and make problem solving difficult.

Attributions: relationship-enhancing vs. distress-maintaining

Relationship-enhancing attributions involve interpreting a partner's positive behavior generously and viewing negative behavior as temporary or caused by circumstances. Distress-maintaining attributions involve interpreting negative behavior as intentional, stable, and representative of the partner's character, while explaining positive behavior away. These interpretations can shape relationship satisfaction.

Gender differences in sexuality

Research has reported average gender differences in some measures of sexual attitudes and behavior, such as self-reported interest in casual sex or number of desired partners. These findings are influenced by social norms, expectations, measurement, and context; averages do not describe every individual and should not be treated as universal rules.

Sexual orientation

A person's enduring pattern of romantic, emotional, and/or sexual attraction. Sexual orientation is not simply a voluntary choice, and attraction and identity may be described in different ways by different people. Same-sex sexual behavior has also been observed in many animal species. Human experiences and the way people identify can vary across cultures and historical periods.