Research has yet to fully explore counselor advocacy for undocumented students and the leadership they use in their advocacy. This study asks the following questions: (1) What motivates counselors to pursue educational access for undocumented K-12 students? and (2) How do school counselors advocate for undocumented K-12 students? We integrate boundary spanning and border crossing leadership theories as a conceptual frame to offer holistic approach for leaders' socially just and inclusive practices concerning undocumented students on the borderlands. This embedded case study uses data from eight K-12 counselors. School counseling-related organizations explicitly detail advocacy competencies and the knowledge base, abilities and skills, and attitudinal dispositions professionals must develop. Knowledge of counselors' leadership advocacy efforts can help prepare preservice leaders and other educators to effectively support undocumented students.