Violence against women in Brazil is any conduct by the aggressor that causes death, physical, psychological or sexual aggression, and can be practised in either a public or private environment. The aim of this bibliographical research is to analyse the effectiveness of the Maria da Penha Law in combating violence against women, in this specific case domestic and family violence, the causes, factors and manifestations of this form of violence, the protective measures for victims of domestic violence, and the effectiveness of the law in legal and social terms. As a matter of public policy, the Maria da Penha Law aims to curb, punish and eradicate any situation of domestic and family violence, as long as the woman reports it. The law has proved effective in punishing aggressors, and through campaigns to raise awareness in society in order to achieve its main objective, which is to eradicate violence against women.