In a setting where husbands wield considerable coercive power, forms of marriage should adapt to protect the interests of women and their families. This paper studies the pervasive marriage custom of watta satta in rural Pakistan, a bride exchange between families coupled with a mutual threat of retaliation. We show that watta satta may be a mechanism to coordinate the actions of two sets of in-laws, each of whom wish to restrain their son-in-laws but who only have the ability to restrain their sons. Our empirical results support this view. The likelihood of marital inefficiency, as measured by estrangement, domestic abuse, and wife's mental health, is significantly lower in watta satta arrangements as compared to conventional marriages, but only after properly accounting for selection.