School leaders play an important role in implementing social emotional learning (SEL) and equitable discipline practices. A Northeastern United States school district initiated the use of SEL programs districtwide to reduce suspensions, and no follow-up has been conducted to explore how school principals adapted implementation to correspond with their leadership practices, nor how these individuals adapted their leadership practices to implement the intervention. Grounded in the SEL and adaptive leadership models, a basic qualitative study was conducted to explore this gap in practice concerning the adaptive leadership behaviors of 10 secondary principals who implemented SEL programs at their schools, including the five SEL competencies of self-awareness, social awareness, self-management, relationship skills, and responsible decision-making. Transcripts of individual semi-structured interviews conducted via Zoom were explored using inductive analysis through a priori and open coding. Findings revealed that principals adapted the SEL intervention through the application of school improvement strategies and by building a strong school culture. Specifically, principals provided SEL training and adapted implementation based on school data and feedback. Principals modified their leadership behaviors by responding to student needs and establishing a school identity. They listened to students, created advisory classes, and made curriculum changes. Positive social change may occur through expanded understanding of school leaders' strategies that support effective SEL program implementation and may assist others seeking to implement SEL programs. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://bibliotheek.ehb.be:2222/en-US/products/dissertations/individuals.shtml.]