Friendships are undeniably important to an individual's health, longevity and wellbeing, but they can be equally important for the health and happiness of a couple. Just as a friend can provide a mirror to the self, another couple can provide a reflecting team that supports or impedes a relationship's growth. Two Plus Two: Couples and Their Couple Friendships offers an important framework for helping couples to have conversations about their friendships with other couples and to enrich their own relationships. When couples agree about how to spend their time alone and with others, they are...