This study investigates the impact of Instructional Leader Partnerships (ILPs) on superintendent leadership practices and their influence on school improvement. Recognizing the significant role of effective leadership in student achievement, this project explored the effects of pairing superintendents with thought partners within a regional educational service district. The study aimed to improve district and school leadership by focusing on superintendent practices that drive principal effectiveness, teacher performance, and student learning. This research builds upon prior work highlighting the importance of job-embedded professional learning for building leaders and the need for central office support in developing instructional leadership capacity. The study explored the following research questions: (1) How to increase leader capacity for cohesive and collaborative leadership in support of improving teaching and learning for all? (2) How do superintendents influence the improvement of instruction? (3) What impact does leadership coaching/thought partnering have on superintendents' practices? (4) What are the behaviors that validate/invalidate the work of instructional leadership? Utilizing a case study design, data were collected through semi-structured interviews using the Concern-Based Adoption Model (CBAM), as other relevant artifacts. Findings revealed that the ILPs significantly influenced superintendent practices, promoting a shift towards collaborative leadership, data-driven decision-making, and a focus on instructional improvement. The study highlights the value of dedicated thought partners in addressing the inherent isolation of the superintendent role and fostering reflective practice. The results offer insights into effective strategies for cultivating leadership capacity at the district level and its subsequent impact on school-level leadership, teacher effectiveness, and student learning.