It is probably true to say that bullying is the psychosocial phenomenon which has attracted the most attention in academic circles over the last ten years. It affects approximately three to five percent of adolescents from twelve to eighteen years of age worldwide to a serious degree and up to twenty percent of this population to a lesser degree. The long and short term effects of bullying are considered to be extremely damaging. The importance of this phenomenon is that it may give rise to low self-esteem, anomie, depression, isolation, psychosomatic symptoms, failure at school and in extreme cases, it may result in suicide and future incidences of bullying in the workplace and within the home. As the number and the seriousness of incidents increases, many parents worry that the problem is spiralling out of control. In recent years, there has been a proliferation of publications on bullying, with an emphasis on how, when and where it occurs, but not on the factors which cause it. This meta-analysis studies the influence of five social environmental variables: neighborhood, family, school, gender-age and the mass media, considered on both an individual and interactional level, as their effects are often augmented when two or more variables are examined together. The concept “bullying” encompasses both individual and collective aggression and individual and collective victimization.