Strategic planning is one of the major strategies for improving secondary school performance in Kenya. However, the implementation of strategic planning has been faced with challenges that need to be investigated. This study investigated the influence of stakeholder involvement, availability of financial resources, leadership styles and technical competence on the implementation of the strategic planning policy in secondary schools within Meru Central District. The study adopted a descriptive research design and a stratified random sampling technique to select 334 respondents comprising of 17 Principals, 114 teachers and 203 members of school Boards of Governors. The data was collected using a questionnaire and the Statistical Package for Social Sciences (SPSS) computer program aided in analysis. Inferential statistics of Regression analysis model was used to test the hypothesis. The study concluded that technical competence, financial resources, stakeholder involvement and leadership styles had a significant relationship with the implementation of the strategic planning policy. The study recommends that policy makers at the Ministry of Education improve the implementation of the strategic planning policy in secondary schools through pointing out loopholes in the implementation of the strategic planning policy in schools, principals to create a higher level of stakeholder?s involvement in any further strategy development and review. It is also critical that a review is done to distinguish between strategic plan implementation and other performance and quality management tools, besides institutionalizing policies so that their guiding philosophies are shared across the faculty membership. Further study can also be executed on the effectiveness of the strategic management plans being implemented in the Secondary schools. Key Words: Strategic Planning, Policy, Technical Competence, Stakeholder Involvement.