This study investigated whether clinical couples' levels of commitment to their relationship and their tendencies to make negative attributions about their partner are related to their use of constructive and destructive behavior during couple conflict. Secondary analyses were conducted on assessment data from 52 couples who sought couple therapy at a university-based clinic. Based on self-report data and coded observations from a 10-minute communication sample completed by the couple, the results support the hypotheses that greater use of negative attributions is correlated with greater use of destructive behaviors, and increased levels of commitment are related to greater use of constructive behaviors. Contrary to expectations, commitment was not a significant moderator of the relationship between negative attributions and destructive behavior during conflict. The results, including specific gender differences, have important implications for effective couple therapy and future research on couple conflict.