The republic of Kenya through the ministry of health established Hospital Management Boards(HMBs) in the early 1990s. This was among her decentralized strategies that were common to many other developing countries. The board was set up to work with the now County Health Management Boards(CHMBs), Hospital Management Teams (HMTs) and the local community, so as: To give community interest on matters health planning first priority; To work with the County Health Management Teams (CHMTs) to harmonize and observe the execution of health initiatives by government and non-government organizations; To recognize problems associated with policy enactment and possible solutions required; To promote cost-sharing and public literacy on health. The effectiveness of the Hospital Management Boards (HMBs) in the governance of hospitals is a challenge that needs thorough investigation putting in mind that the process of constituting neither them nor their effectiveness has neither been studied at length. The goals of this research objectives of the study were to assess the influence of the board’s best practices, on the performance of the mission hospital. The study employed the descriptive survey research technique. The research chose a sample size of 400 individuals including: 13 Hospital Management Board members; 8 Hospital Management Team members; 21 HODs & Unit In- Charges; 20 Administrative Staff; 252 medical staff and 86 supportive staff. A sample size of 200 participants were selected using stratified random sampling technique. Questionnaires were majorly employed to gather information. The viability of tools used was examined using the test- retest method and acceptable levels set at r>0.7 while the validity was determined using expert opinion. Quantitative data was explored by help of descriptive statistics including means, frequencies, ratios and percentages. The hospital management board was found to have adopted the best management practices.