The adolescent developmental period is marked by increased social and academic demands, as well as biological changes that lead to profound shifts in sleep and circadian timing. Circadian misalignment, short sleep duration, and irregular sleep patterns are prevalent among adolescents and are linked to a wide range of negative outcomes, including impaired emotional regulation, diminished academic performance, and increased cardiometabolic disease risk. While efforts to promote adolescent sleep health have grown, the multidimensional nature of circadian sleep health remains underassessed in both research and clinical contexts. This review provides conceptual definitions of key circadian sleep health concepts, synthesizing current best practices for measuring circadian sleep health in adolescents across self-report, behavioral, and physiological domains. We organize assessment strategies around three key circadian constructs-chronotype, circadian timing, and circadian alignment-and describe validated tools for each. In addition, we explore measurements of contextual factors influencing circadian function, such as light exposure, meal and exercise timing, pubertal status, and genetic predispositions. Throughout this review, we emphasize the value of a multimodal approach that combines subjective experience with objective biological and behavioral data to improve clinical utility and advance the understanding of circadian sleep health. We conclude by outlining directions for future research, including the need for validated, developmentally appropriate tools and the integration of wearable technologies to improve accessibility and clinical utility. By consolidating core concepts and methodological tools, this review aims to assist researchers and clinicians selecting appropriate assessment strategies and tailoring interventions to improve adolescent circadian sleep health.
