The role of teachers continues to change as they receive new responsibilities and roles within their schools. Through engagement in professional development, teachers receive unique opportunities to become leaders within their schools by promoting student achievement and enhancing school practices and policies, particularly for STEM education. However, due to a shortage of qualified teachers in STEM education, teacher leaders are becoming even more imperative for supporting learner growth and promotion of STEM related fields. Further, STEM teacher leaders provide mentorship to their colleagues in their integration of STEM curriculum and innovative technologies that enhance student learning. This chapter highlights the importance of teacher leaders and their positive impacts in furthering STEM education initiatives and activities within their schools and districts.