Behavior analysts frequently lament the lack of global impact of behavior-analytic philosophy and application, especially in "mainstream" domains such as general education, healthcare, or policy. This panel will share the achievements and challenges of a behavior-analytic program that is widely used in a mainstream context. Headsprout, an online program created by behavior analysts, teaches early reading and reading comprehension and is used in schools around the globe. Panelists will discuss how Headsprout became "mainstream," as well as the difficulty most "laypeople" have understanding the design behind the program and why it does not follow the approach used by most other instructional programs. Discussion will cover objections from traditional educators, the increasing requirements and challenges facing all instructional programs (regardless of philosophy), and how Headsprout has managed to maintain and increase adoption across the years (including effectiveness data and what has been learned through wide-spread implementation). Behavior analysis can make an impact through wide-scale applications, and the experiences of Headsprouts creators and implementers might help inform scientists and practitioners who aim for that goal.