This action research addressed three primary questions: 1) Does developing the EI of school leaders improve staff job satisfaction? 2) Does developing the EI of school leaders enhance the school climate? 3) Does developing the EI of school leaders lead to increased student achievement? Pre- and post-intervention surveys were conducted using the Job Satisfaction Survey (JSS), the Job Satisfaction Survey (TEIQUE), and the ED School Climate Surveys (EDSCLS). Interventions were implemented for the school leadership team with the assistance of a behavior consultant and focused on developing emotional intelligence. Student performance was measured using Spring 2024 standardized test results compared to Spring 2023 results. Dependent t-tests evaluated the impact of EI development on staff job satisfaction, school climate, and student achievement. Descriptive and inferential statistical analyses were used to summarize the data and explore relationships between EI development in leadership, staff job satisfaction, school climate, and student achievement. Correlation analyses provided deeper insights into these relationships. Though not statistically significant, the findings revealed increased job satisfaction, improved school climate, and enhanced student achievement. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://bibliotheek.ehb.be:2222/en-US/products/dissertations/individuals.shtml.]