Technology-facilitated personalized learning (PL) approaches have become increasingly common in K–12 schools across the United States, and as distance learning becomes more common during the coronavirus disease 2019 (COVID-19) pandemic, they are poised to become even more widely used. PL aims to create individual learning experiences and pathways for students. PL takes a wide variety of forms and typically involves changes to instructional materials and practices as well as school and system-level organizational conditions. These changes are often facilitated by technology. Despite the popularity of PL, little data exists on the prevalence of PL practices, and there is only limited understanding of the conditions needed to support high-quality PL implementation, particularly in high schools. This report presents findings from RAND's 2018 American Teacher Panel. As part of the survey, a nationally representative sample of high school teachers responded to questions about their use of instructional practices consistent with PL and access to necessary supports. The findings should be useful to practitioners, professional development and support providers, researchers, and policymakers who are interested in understanding how high school teachers are using PL practices and which supports and resources they need to use them effectively.