Abstract: TV content ratings systems have been put in place by many countries as a way of reducing media effects on children. The relation between media effects and TV content ratings systems has been substantively analyzed within the social scientific community. This article provides such an overview. First, it lays out some of the main theoretical models of media effects, that is, the social cognitive theory and the cultivation theory. Second, it describes existing empirical research. In this section, it demonstrates the origin of content ratings systems and these ratings development over the years, parents understanding of TV content ratings and the factors that influence a parents understanding of these ratings, parental implementation of PG in practice and children’s interpretation of their parents’ mediation behavior. Third, the article points out future fields of research.