Based on theory and research on learning environments, the Delaware School Climate Survey-Teacher/Staff (DSCS-T/S) was developed to provide schools with a brief, psychometrically sound measure of teachers' perceptions of school climate. Multigroup confirmatory factor analyses, conducted on a sample of 5,781 teachers, support staff, administrators and other staff in 132 schools, showed that a bifactor model consisting of seven specific factors best represented the data. Those factors were Teacher-Student Relations, Student-Student Relations, Teacher-Home Communication, Respect for Diversity, School Safety, Fairness of Rules, and Clarity of Expectations. Measurement invariance was found across grade levels (i.e., elementary, middle, and high schools) and subgroups of respondents (i.e., teachers, instructional support staff and noninstructional staff). As evidence of concurrent validity across grade levels, nearly all scores, aggregated at the school level and correlated significantly and negatively with suspensions/expulsion rates and positively with academic achievement. The DSCS-T/S is likely to be useful to schools interested in assessing school climate and the effects of various programs, such bullying prevention programs, that target the seven dimensions of school climate measured.