Research from several sources has unequivocally shown that close relationships are strongly linked to health and well-being. For example, in terms of physical health, large-scale epidemiological studies have demonstrated that social isolation is associated with a substantial increase in all-cause mortality risk (eg, Berkman & Syme, 1979; House, Landis, Umberson, 1988). Studies focused on specific physiological systems have found that poor-quality relationships or a lack of social ties are associated with poorer functioning cardiovascular, immune, and endocrine systems (see Uchino, Cacioppo, & Keicolt-Glaser, 1996, for review). In terms of well-being, it has been well-established that positive close relationships are closely tied to happiness and satisfaction with life (eg, Berscheid & Reis, 1998; Diener & Seligman, 2002). These links do not exist solely on the pages of empirical journals; they are clearly recognized by the public. For example, people routinely cite their close relationships as their most significant or meaningful areas of life (eg, Little, 1989; Sears, 1977). In short, both the empirical data and common experience support the idea that forming and maintaining stable and positive close relationships is a critical component of health and well-being. Moreover, the human condition cannot be understood without a careful understanding of close relationships (eg, Baumeister & Leary, 1995) and how the mind evolved to develop and maintain these ties.

Even though the field of close relationships is a relatively young science, scholars have made considerable progress in understanding processes that unfold in close relationships. The lion’s share of this research has focused on processes that undermine close relationships and the links between poor-quality social relationships or social isolation and negative outcomes. However, over the years there have been several notable exceptions to the focus on negative relationship processes, and recently researchers have begun to pay closer attention to positive processes in relationships. In this chapter, we first take stock of work that has focused on processes that promote high-quality relationships and the role that these processes play in health and well-being. We then discuss areas that we see as ripe for future research on positive processes in close relationships that are likely to shed light on important links to health and well-being.