Past research have pointed out that excellent strategies have been written but extremely small have been accomplished in their implementation. It has additionally been proposed that only 10% of formulated strategies are successfully implemented. However, crafting the best strategy is not the end in itself but the ultimate result will only be realized once the plan is successfully implemented. A strategic plan is a management tool that is used to transform organizational objectives into actions. The purpose of this study was to establish the effects of strategic plan implementation on organizational performance: a case study of public Secondary Schools in Kenya. The country in the recent past has experienced challenges like student declining performance in national examinations and increased student enrolments this implies that student cannot be able to join higher learning institutions which mean their future is blurred. The specific objectives were to analyze the effects of leadership style and communication in successful implementation of the strategic plans. A descriptive survey design using stratified sampling was used. The study population comprised of the school managers including teachers, principals and deputy principals serving in selected schools. Primary data was collected through questionnaires that were administered through "drop and pick later" method while secondary data was gathered from relevant Ministry of Education, Teachers Service Commission (TSC) and Government of Kenya publications like the Strategic plan, TSC Act, Ministry of Education (MoE) records. Quantitative data was analyzed though descriptive statistics and multiple regression analysis. Quantitative data was presented using bar graphs, pie charts and frequency distribution tables.