This study focuses on the social position and the degree of being bullied of pupils with behaviour problems fully included in regular education and on their teachers' assessments on social integration and bullying. The study sample consisted of 25 9- to 12-year-old pupils with behaviour problems and their peers without special needs participating in full-time regular education in the north of The Netherlands. Data gathering was performed using pupil and teacher questionnaires and a sociometric test. Results indicate that compared to their peers without special educational needs (SEN), the pupils with behaviour problems in this study were included less socially. The study further shows that about half the teachers participating in the study have a too positive view on the social position of these pupils. These teachers tend to seriously underestimate both the frequency with which pupils are being bullied and the frequency with which these pupils actively bully their peers.