The study found that schools composed predominantly of students with low SES had four times the number of disciplinary referrals for violence, up to three times the number of referrals for classroom behavioral problems, and nearly twice the number of referrals for violations of campus and school rules compared with schools whose students were predominantly from high SES families. Among low SES schools, disciplinary referrals were higher in elementary, middle, and high schools compared with high SES schools. The findings suggest that safe-school policies and schoolwide comprehensive violence-prevention programs are especially important for schools in low SES neighborhoods. Data for the study were obtained from a countywide school district on the west-central coast of Florida. The study sample consisted of 14,905 students in 12 schools who were representative of the district's 111,000 students in 156 schools. The sample contained six schools located in high SES neighborhoods and six schools located in low SES neighborhoods. Participation in the free or reduced lunch programs was the measure of low SES. Data were collected during a 3-year period, beginning in the fall of 1999 and ending in the spring of 2002. Disciplinary referrals pertained to 36 categories of offenses that involved teachers or other school staff referring students to school administrators for problem behaviors that encompassed policy referrals, violence, classroom behaviors, campus and schools rule violations, and misconduct on a school bus. 6 tables and 41 references