AbstractThe effects of attachment style and presence of a romantic partner on psychophysiological responses to a stressful laboratory situation were examined in a sample of 34 college women involved in serious dating relationships. In two separate laboratory sessions, one with romantic partner present and one with partner absent, participants were led to anticipate a stressful situation. Heart rate and systolic and diastolic blood pressure levels were recorded during baseline and stress periods in each condition. Significant three‐way interactions showed that both avoidant and anxious participants in the partner‐present condition evinced elevated psychophysiological responses to the stressor (relative to baseline), in contrast to these groups in the partner‐absent condition and secure and nonanxious participants in both conditions. Findings are compared to those of previous research on attachment‐style differences in proximity‐seeking behavior in a similar laboratory situation, and they are interpreted in terms of the approach‐avoidance conflict experienced by insecure people when faced with a stressful situation in the presence of their romantic partners.