A critical next step in advancing our understanding of teacher practices that can equitably engage and support learning in diverse classrooms is determining the effectiveness of culturally responsive interventions. Yet, quantitative measurement indicators of the effectiveness of culturally responsive teaching interventions are scarce. Most research relies exclusively on self-reports, with limited attention to issues of social desirability, and few studies observe teacher practices. Data come from 142 K-8 teachers in six schools who were assessed via the Assessing School Settings: Interactions of Students and Teachers (ASSIST), an externally-conducted observation, and who also provided self-report data of cultural responsiveness. Analyses indicated that teachers self-reported higher rates of culturally responsive teaching strategies than were observed on the ASSIST. There were, however, significant associations between observations and teachers' ratings of self-efficacy. Findings suggest a need for additional research to develop and validate efficient, multi-informant approaches for assessing cultural responsiveness in the classroom. [This paper was published in "Psychology in the Schools" v52 n6 p533-548 2015.]