Most researchers into bullying agree on its social implications and on some inner aspects of the aggressive situations. Methods of identifying bullying among peers used to be very costly in time and effort. In order to simplify the task, the Bull-S questionnaire has been elaborated. After its confirmation as a usable instrument in Spanish schools, we attempted to find out whether it could also be a good tool in foreign schools, by applying it to both an English and a Spanish sample. Results showed very high similarity between samples, which allows us to say that the aspects measured by the questionnaire are the same in both samples. First, we did not find significant differences in the extent of bullying in schools. Second, an item-by-item comparison showed significant differences between means in only: "Leave out of activities and games." From a sociometric perspective, rejection is presented as associated with bullying and especially linked to victimisation, and acceptance is associated with those pupils not involved in bullying. Finally, factorial analyses confirmed that variables conformed to a different structure for bullies, for victims, and for not-involved pupils. These different structures are quite similar in both countries.