Social anxiety is marked by viewing social interactions as competitive, hypervigilance to signs of social threat, and avoidance of interactions that may result in social rejection. Therefore, social anxiety should relate to: (1) greater hostile feelings toward others, (2) heightened perceptions of hostility in others, and (3) relatively low levels of violence and aggression. To date, however, little is known about these relationships. In four independent non-clinical samples (total N=2643), we examined relationships between social anxiety, hostility, and aggression using a range of measures that included both self-report and behavioral assessments. In Study 1, social anxiety correlated positively with feeling hostile toward others. In Study 2, social anxiety correlated positively with hostile perceptions of others. In Study 3, social anxiety was related to less positive attitudes toward behaving violently toward one's relationship partner. In Study 4, social anxiety was related to less aggressive behavior, as indicated by less intense and prolonged noise blasts delivered to a fictitious opponent. Taken together, these four studies paint a picture of socially anxious people as bracing for the worst by feeling and perceiving hostility in the social environment, but behaving the best by refraining from aggression and violence.