An intimate relationship is a particularly close interpersonal relationship. It is a relationship in which the participants know or trust one another very well or are confidants of one another, or a relationship in which there is physical or emotional intimacy.

Intimate relationships play a central role in the overall human experience (Miller, Perlman & Brehm, 2007). Humans have a universal need to belong which is satisfied when intimate relationships are formed (Perlman, 2007). Intimate relationships consist of the people that we are attracted to, whom we like and love, romantic and sexual relationships, and those who we marry and provide emotional and personal support (Miller et al., 2007). Intimate relationships provide people with a social network of people that provide strong emotional attachments and fulfill our universal needs of belongingness and the need to be cared for (Miller et al., 2007).

The systematic study of intimate relationships is a relatively new area of research within the field of social psychology that has emerged within the last few decades (Miller et al. 2007). Although the systematic study of intimate relationships is fairly recent, social thought and analysis of intimate relationships dates back to early Greek philosophers (Miller et al. 2007). Early scholarly studies were also interested in intimate relationships but were limited to dyads or small groups of people in the public and narrowly examined behaviours such as competing and cooperation, negotiation and bargaining and compliance and resistance (Miller et al., 2007).

Physical intimacy is characterized by romantic or passionate love and attachment, or sexual activity.

Physical and emotional intimacy

main: Intimacy

Love is an important factor in physical and emotional intimate relationships. Though the term is notoriously difficult to define, any thoughtful inquiry into the subject will show it to be qualitatively, not only quantitatively, different than liking, and the difference is not merely in the presence or absence of sexual attraction. There are two types of love in a relationship; passionate love and companionate love. With companionate love, which potent feelings diminish but are enriched by warm feelings of attachment, an authentic and enduring bond, a sense of mutual commitment, the profound knowledge that you are caring for another person who is in turn caring for you, feeling proud of a mate's accomplishment, and the satisfaction that comes from sharing goals and perspective. Where in contrast with passionate love it is marked by infatuation, intense preoccupation with the partner, strong sexual longing, throes of ecstasy, and feelings of exhilaration that come from being reunited with the partner (Hatfield & Rapson, 1993).

People who are in an intimate relationship with one another are often called a couple, especially if the members of that couple have ascribed some degree of permanency to their relationship. Such couples often provide the emotional security that is necessary for them to accomplish other tasks, particularly forms of labor/work.