Perspective taking is theorized to help sustain satisfying social relationships by promoting prorelationship responses that reduce harmful negative behaviors in relationship interactions. The present studies provide the first tests of whether perspective taking predicts less negative behavior within couples' daily and lab-based conflict interactions. In Study 1, individuals (N = 77) rated their perspective taking and their own and partner's hurtful, critical, and distancing behavior each day for 14 days. In Study 2, couples (N = 78 dyads) completed the same daily measures for 21 days. In Study 3, couples (N = 143 dyads) engaged in a lab-based video-recorded discussion of their most serious conflict. Each dyad member reported on the degree to which they engaged in perspective taking, and their own and their partner's negative behavior, during the discussion. Objective coders also rated the degree to which both partners exhibited negative behavior during the discussion. Actors' perspective taking was associated with actors' lower negative behavior as reported by actors (Studies 1-3) and partners (Study 2) and as rated by observers (Study 3). Significant interaction effects also suggested that actors' perspective taking attenuated how much actors behaved more negatively as their partners behaved more negatively, although the moderating pattern was weaker within daily reports (Studies 1 and 2) compared to couple's observed conflict interactions (Study 3). The attenuating effects of perspective taking were independent of commitment, satisfaction, self-esteem, and attachment insecurity. These studies provide new evidence that facilitating perspective taking may reduce common, destructive behaviors that can harm couple relationships. (PsycInfo Database Record (c) 2024 APA, all rights reserved).