A recent synthesis of research from the last two decades confirms that principals can have a significant impact on student learning outcomes, accelerating annual student learning by more than two months. Effective principals focus on high-leverage instructional activities, build a productive culture and climate, facilitate collaboration and learning communities, and strategically manage personnel and resources. This paper focuses on the specific actions that principal supervisors can take to build the capacity of principals as leaders of instruction in their schools. A growing body of research points to principal supervisors as a key lever for change when they shift from a focus on compliance to a focus on coaching. Four solutions are described that principal supervisors in partner districts used to help principals address instructional leadership challenges: (1) Be a visible partner and model being a lead learner; (2) Develop a common vision and consistently use a shared language that describes expectations for principals around the instructional leadership aspects of their role; (3) Establish a coaching, feedback, and support system that is aligned with expectations in evaluation; and (4) Create opportunities for collaboration and capacity-building.