The aim of this study was to determine the prevalence of bullying in its various forms from the perspective of all of the individuals involved (victims, bullies, and witnesses) and to explore its distribution as a function of gender. The study had a correlational design and used a representative sample of 1500 Spanish students attending compulsory secondary education in the academic year 2007-2008. It applied an instrument measuring different types of bullying, taken from the studies conducted by Díaz-Aguado, Martínez, and Martín (2004) and the Defensor del Pueblo (Spanish Ombudsman's Office)-UNICEF (2007). The findings reveal that all the types of bullying considered take place at school and that there is an inverse relationship between the severity and the prevalence of bullying behaviors, with verbal abuse proving to be the most common type of abusive behavior. Boys are involved in all kinds of bullying incidents as bullies significantly more often than girls are, except in cases involving 'talking about someone behind their back'; in these situations, girls are involved significantly more often as bullies than boys are. As for victimization, boys are victims of direct physical abuse significantly more often than girls are, while girls are more often the subject of malicious gossip.