Literature was reviewed about how synchrony occurs in infant-parent dyads, in emotion, and physiologically in couple dyads. Social baseline theory suggests that both conversation and interpersonal touch confer benefits by reducing burden on the participants through coregulatory processes. The current study examined how affectionate touch and positive conversation influenced physiological synchrony, a potential mechanism of physiological coregulation, in couples. Because synchrony is believed to occur within the autonomic nervous system, in the present study, physiological synchrony was measured using cardiac interbeat interval (IBI) as an indicator of autonomic nervous system activation. Couples were assigned to one of four conditions: interpersonal touch with positive conversation, interpersonal touch without conversation, positive conversation with no interpersonal touch, and neither interpersonal touch nor conversation. We hypothesized that 1) IBI synchrony between spouses within the real data would be significantly higher than within a phase-shuffled version of the data; and 2) synchrony would be strongest in the touch-talk condition, followed by the touch-no talk condition, followed by the talk-no touch- condition, and finally by the no touch-no talk condition. We also investigated whether there was a tendency for husbands or wives to serve as leader or follower in the four conditions. Using windowed lagged cross-correlations, we found that synchrony within the real data was stronger than synchrony within the shuffled data, suggesting that it reflects an ongoing interpersonal process. Next, we found that there was significantly greater synchrony in the touch-talk than in the touch-no talk condition, marginally greater synchrony in the touch-no talk condition than in the no touch-talk condition, and significantly greater synchrony in the no touch-talk than in the no touch-no talk conditions, suggesting that talk, rather than touch, was driving these synchrony levels. We also found that the only condition with a significant level of leading-following pattern was the no touch-talk condition. More husbands than wives led the covariation in IBI when couples were conversing but not touching. When touch was included this effect did not occur. Future research should include potential moderators such as marital satisfaction and investigate whether seeing one’s partner influences synchrony.