Over the past 15 years, the Lamat Institute has increased participants’ competitiveness for graduate programs and prepared them for the STEM workforce more broadly. Key components of the Institute include intensive research instruction through summer internships, a winter computational boot camp, academic counseling and mentoring, support for graduate school applications and CV workshops, and astronomy talks and workshops lead by distinguished faculty. In addition, a comprehensive mentoring professional development program is provided to empower mentors and mentees to co-develop a transformative learning space that prepares and inspires mentees for graduate study.