Background: Bullying occurs in all schools. Measuring bullying in schools is complicated because both definitions of bullying and methods for measuring bullying vary. This study compared a brief 12-item Gatehouse Bullying Scale (GBS) with items drawn from the Peer Relations Questionnaire (PRQ), a well-established bullying questionnaire to measure the concurrent validity of the GBS. Methods: Year 8 secondary school students (14 years of age) in metropolitan and regional Victoria, Australia, completed questionnaires assessing being teased, being deliberately left out, had rumors spread about oneself, and/or being physically threatened or hurt. Results: The prevalence of bullying using GBS and PRQ was 57% and 61%, respectively. Percent agreement between the 2 measures was high. Agreement adjusted for chance was moderate (kappa 0.5). The GBS had good to moderate test-retest reliability (rho 0.65). Conclusions: The GBS is a short, reliable tool measuring the occurrence of bullying in schools. As well as a global estimate of bullying, the GBS provides estimates of 2 covert and 2 overt types of bullying which can be useful for schools to better plan interventions dealing with school bullying.