Utilizing reports from both observers and direct targets, the authors examined the role of psychosocial work environment factors in workplace bullying, focusing on the moderating effects of control and support resources against job demands. Our sample was 716 Australian frontline police officers who completed an anonymous mail survey. In a direct test of Job DemandControl-Support theory, the authors found that increased levels of bullying (as assessed by targets and observers) were associated with potentially high stress situations: as job demands increased and as support and control resources decreased. Also, consistent with previous research, most perpetrators were ranked higher than the target, reflecting the role of power in facilitating bullying. Our research is unique in finding evidence for moderating factors within the psychosocial environment and suggests risk assessment of the work environment as an avenue for bullying prevention. Future research should examine more closely the mechanisms underlying bullying within stressful work environments and the reciprocal effect of witnessing and experiencing bullying on psychosocial working conditions.