School counselor roles and responsibilities have changed over time based on changes needed to support students. From being identified as vocational guidance to guidance counselors, these changes have influenced their advocacy for their profession and their students' academic, socio-emotional, college, and career developmental needs. They are now being recognized as school leaders who are change agents with the knowledge and skills to eradicate inequitable policies and practices impacting students, especially those who are marginalized. Although school counselors have the ability to implement systemic change, some demands hinder them from working to close the opportunity gap. This study aimed to explore participants' perceptions of their leadership behavior and practices and their advocacy level in supporting marginalized students. Additionally, the study addressed the time spent on duties and the duties they would prefer to perform before transferring students to alternative or continuation schools. Using transformative leadership theory as the framework, this study examined survey responses from 147 school counselors to examine their perceptions of leadership behavior and practices in the school setting. Quantitative results indicated that the respondents perceived they possessed a high level of interpersonal influence, social justice advocacy, and professional efficacy compared to resourceful problem solving and systemic collaboration from the leadership dimensions on the School Counselor Leadership Survey. Findings also indicated the impact of years of experience on increased leadership perceptions regarding systemic collaboration, professional efficacy, and social justice advocacy. Results suggested that those who work with students before they are transferred to an alternative educational program prefer to provide interventions and services to students rather than focus on non-counseling duties that are commonly assigned to them. Qualitative findings from 117 participants indicated several themes including the importance of administrators' involvement, staff collaboration, and family participation in supporting marginalized students and addressing inequitable policies and practices. Themes for participants who work to help students transfer to an alternative or continuation school include the need for more support as well as increased collaboration between school staff and students' families. Implications and recommendations for policy and practice are discussed. [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://www.proquest.com/en-US/products/dissertations/individuals.shtml.]