In response to the growing interest in mind-body practices as preventative, therapeutic and educational interventions, the current work describes the instrument development and validation process to address a gap in yoga research. Yoga is a mind-body practice used in clinical and school settings that uses an integrative curriculum which simultaneously targets skill development/ maintenancein physical, cognitive and emotional realms. Yoga is heterogeneo, us as there is variability across styles and interventions. Yoga is also educational, as there are integrative skills being learned The heterogeneous and educational nature of yoga necessitates reporting that accounts for variability in the instruction across instructors of an intervetnion Observed instruction is one key element to understanding the heterogeneity of yoga. Influencing factors of instructional choices, such as beliefs should also be explored. While there is a validated instructional observation instrument for identifying components of a yoga intervention, a tool is needed to distinguish influencing factors of instructor choice. Modeled after research on school teacher beliefs and values linked to student achievement outcomes, the newly developed instrument provides a tool for measuring yoga instructor beliefs about yoga and yoga instruction. The sequential mixed methods steps in the development and validation of scores from the Yoga Instruction Beliefs Scale (YIBS) are described in separate manuscripts.