Bullying and harassment negatively affect the learning environment, and school principals can make a difference. Previous research has found that teachers see having a supportive principal as critical to changing school climate. Yet not all principals may have the experience, skills or knowledge to address lesbian, gay, bisexual or transgender (LGBT) student issues. In order to get a clearer understanding of the principal's perspective, the Gay, Lesbian and Straight Education Network (GLSEN) collaborated with NASSP (the National Association of Secondary School Principals) on a study exploring the perspectives of elementary and secondary public school principals on student bullying and harassment and on the policies, programs and training that principals have instituted in their schools to address these issues. A survey conducted by Harris Interactive revealed that K-12 principals underestimate the harassment LGBT students experience in schools. Although principals report their schools engage in anti-bullying/harassment efforts, most do not specifically address school safety for LGBT students. (Contains 40 tables.) [This publication was produced by the Gay, Lesbian and Straight Education Network.]