Human resources are considered valuable in any organization as they ensure every task is done smoothly. However, if these human resources are not well equipped with the right equipment, techniques and knowledge on how to perform their duties, they cannot be productive, and this is where training comes in as a solution to solving these problems. This study aims to show how training contributes to improved employee performance at Tanzania Police Headquarters. The study was guided by open innovation theory and organizational development theory. The study adopted a case design because it took a short time and was constructed as a single case study of the Tanzania Police Headquarters (TPF). Both probability and non-probability sampling methods were beneficial in helping the purpose underlying this study. The target population was the Tanzania Police Force (TPF) headquarters employees in Dar es Salaam city. The 125 sampled TPF employees were drawn from three nominated departments to offer information in the study using questionnaires, interviews, and literature reviews as instruments of data collection. Data was analyzed using social science statistical package. The findings revealed that in the study area, different types of training were provided to employees such as on job training, promotional training, refresher training, technological training and orientation training. Employees at TPF revealed that training has increased the morale of employees, reduced employee turnover, improved staff retention and improved job satisfaction as well as improved skills which have improved performance. Data findings indicated that the absence of training needs assessment, outdated curriculum, limited facilities; incompetent trainers and insufficient funds were barriers to conducting training. The study concluded that training has increased the morale of employees, reduced employee turnover, improved staff retention and improved job satisfaction as well as improved skills which has improved performance. It was recommended that TPF should establish strong strategic plans to support training and development to employees as well as reduce hindrances facing the proper utilization of training and all these can be considered when there is a strong policy for training and evaluation of training needs assessment.