The key relationship dynamics of communication, conflict, and commitment were investigated using data from a randomly sampled, nationwide phone survey of adults in married, engaged, and cohabiting relationships. Findings on communication and conflict generally replicated those of studies using more in depth or objective measurement strategies. Negative interaction between partners was negatively associated with numerous measures of relationship quality and positively correlated with divorce potential (thinking or talking about divorce). Withdrawal during conflict by either or both partners, thought quite common, was associated with more negativity and less positive connection in relationships. The most frequently reported issue that couples argue about in first marriages was money, and in re-marriages it was conflict about children. Overall, how couples argue was more related to divorce potential than was what they argue about, although couples who argue most about money tended to have higher levels of negative communication and conflict than other couples. Further, while the male divorce potential was more strongly linked to levels of negative interaction, the female was more strongly linked to lower positive connection in the relationship. Consistent with the commitment literature, higher reported commitment was associated with less alternative monitoring, less feeling trapped in the relationship, and greater relationship satisfaction.