The concept of entrepreneurial orientation (EO) attracts considerable attention in the organizational literature. Focusing on issues related to measurement of EO and using a three-pronged framework to organize the growing diversity of EO measures, the authors conduct a systematic literature review on how EO is captured and assessed in the empirical literature. Specifically, the authors classify 551 empirical works according to the approach to measurement (i.e., managerial perceptions, content analysis, and resource allocations) which allows the authors to document and critically analyze prevalent measurement practices within the literature. Based on the synthesis, the authors identify key measurement-related tensions that may inhibit cumulative knowledge development in the area of EO, such as ad hoc modification of seminal scales and lack of theoretical clarity with respect to measurement. Additionally, the authors find that research into the antecedents of EO as well as causality and temporality of the phenomenon is underdeveloped, which the authors attribute to scarce use of mixed methods. The authors conclude chapter by discussing the challenges involved in measuring EO and offering possible recommendations for future inquiry.