In this commentary, Cornell and Bradshaw report decades of research in school psychology have brought attention to the culture of peer bullying and harassment that was a largely neglected problem in most schools. At the same time, research on the school environment has brought recognition to the importance of a safe and supportive school climate. The authors point out that more than a decade ago in a special issue of "School Psychology Review," Espelage and Swearer (2003) presented a cogent analysis of the state of research on bullying in American schools. They identified some key challenges in the conceptualization and measurement of bullying and in the development of a social-ecological approach to intervention. The first challenge raised was the need for consensus in defining and measuring bullying. A second challenge identified was the need for more attention to relational aggression and gender differences in bullying behavior. The final two challenges were to pay more attention to the bystander roles and group processes that promulgate bullying behavior and to pursue a social-ecological approach to bullying that considers the interaction of individual characteristics and group factors. As the assessment of school climate becomes a more widespread and routine practice in schools, school psychologists will have valuable information to guide the implementation of programs to facilitate the evolution of schools toward more inclusive and tolerant environments in which all students feel respected and supported.