Comparatively little is known about the nature, incidence and correlates of bully/victim problems in the Northern Ireland school system. The study examined the prevalence of self-reported experiences of bully/victim problems and the relationship between such experiences and levels of stress and psychological well-being among a representative sample of sixteen-year olds who participated in the 2005 "Young Life and Times" survey. Bully/victim problems among these adolescents were pervasive. Personal experience of involvement in bully/victim problems was associated with self-reported stress and impaired psychological well-being. Findings are interpreted within the context of previous data from YLTS and the wider national and international literature on bully/victim problems. (Contains 2 tables.)