While the previous chapter focused on the early years of a couple's marriage or partnership, this chapter explores couples who are in their middle years. Great variability exists for couples in these middle years of marriage. Some are in a first marriage or partnership, whereas others have remarried. (We address divorced couples in a later chapter.) Couples today, especially those who complete college or graduate school, tend to delay having children while completing their education. They may become parents for the first time in their 30s or even 40s. Such couples may have married later or established themselves as a couple years before having a child. Other couples in this stage of marriage may not have children, due to choice or medical difficulties, and find their relationships between themselves and their friends who do have children have changed. Those with children may start to seek out couples with children just as those without children may prefer the company of those who have not traveled down the child path. Older couples with children at the end of this middle stage often see their children becoming more independent in their teen years and then leaving home, potentially freeing up more time for their adult friendships.