In this chapter, we describe how the Appalachian Mathematics Partnership (AMP) used the PRIME Leadership Framework (National Council of Supervisors of Mathematics, 2008) to inform professional development activities that respond to teachers' content and pedagogical needs and cultivate emerging mathematics leadership. The PRIME Leadership Framework fit philosophically with the goals of the project, identifying the reflective, knowledgeable leader, including teachers as classroom leaders, as essential to committing knowledge to action. Further, AMP aligned the leadership framework with its underlying principles for professional development of engaging teachers in meaningful content connected to classroom experiences and high leverage teaching practices, providing a model for how projects can embed meaningful interpretations of leadership in content-oriented professional development.