This report describes and provides research and scholarly support for a core practice of teaching—eliciting student thinking (EST)—that is the target for a performance assessment contributing 1 component of the ETS National Observational Teaching Examination (NOTE) assessment series. The purpose of this report is to review the evidence supporting the importance of this practice for teaching, including how it has been conceptualized, studied, and represented in consensus literature on teaching. Then, the report describes the EST performance assessment together with the rationale for its design.