In the current paper, we hypothesized that people who are high in neuroticism (N) share a motivational predisposition to react vigilantly to threatening cues, most of which tend to be social in humans. In three studies, support for this prediction was found: based on cross-sectional and diary data, it was found that the self-esteem (SE) of individuals high in N decreases more in response to perceptions of relationship conflict and low relationship quality than that of emotionally stable ones. In a study of people's reactions to imagined threats, neurotic individuals showed a heightened sensitivity to both nonsocial and social cues, though reactions to social cues were somewhat more pronounced. Results are consistent with principles from evolutionary and process-oriented personality psychology. Copyright © 2008 John Wiley & Sons, Ltd.