The aim of this paper is to define the monitoring of the work performance of employees and to show the importance of a continuous and organized system of monitoring and evaluating the workforce. Monitoring work performance greatly affects the overall success of the organization, given that it provides managers and administration with key information about the real condition, qualifications and motivation of their employees. A manager without knowledge of how employees perform certain tasks, what abilities they have, how successfully they solve problems, etc. cannot successfully make decisions and plan and organize business activities. By choosing one or several methods for monitoring work performance, information is obtained about the work efficiency of employees, which, through further analysis, is used for different purposes, such as, for example, differentiation of employees or determination of the variable part of the salary. The key factor in the evaluation are the evaluators, who must be adequately trained, conduct the evaluation fairly and transparently, following pre-determined rules. Despite the numerous shortcomings that appear in the evaluation process, mentioned in the paper, continuous and systematic evaluation ensures that these shortcomings are avoided and that they do not affect the overall benefits that the process brings. The most important purpose of monitoring and assessing work performance is to improve work performance and achieve the goals of the organization.