{Reference Type}: Journal Article {Title}: Emotion Regulation Flexibility in Adolescents: A Systematic Review from Conceptualization to Methodology. {Author}: Haag AC;Bagrodia R;Bonanno GA; {Journal}: Clin Child Fam Psychol Rev {Volume}: 0 {Issue}: 0 {Year}: 2024 Jul 14 {Factor}: 7.41 {DOI}: 10.1007/s10567-024-00483-6 {Abstract}: Considerable attention has been devoted to the concept of flexible emotion regulation, which de-emphasizes the importance of any specific regulatory strategy in favor of the flexible deployment of strategies in response to specific situational challenges. The bulk of research in this area has been conducted on adult samples. Research on emotion regulation flexibility (ERF) in youth has been documented in only a limited number of studies and using various definitions. This systematic review aims to gather and summarize different conceptualizations and methodological approaches of adolescent ERF. We incorporate these findings into a general framework to understand ERF and its role in adolescents' emotional, behavioral and social functioning. Adhering to the PRISMA guidelines, 11 studies were included in the review. While ERF has been defined in various and inconsistent ways, the included studies utilized conceptualizations from two overarching domains: the regulation of expressed emotion and the repertoire of emotion regulation strategies. Promising approaches and future directions will be highlighted.