Measuring efficiency and effectiveness of public administration is becoming an increasingly relevant topic. The way in which public services are delivered is becoming more and more important. The purpose of the theoretical section of the thesis was to present the organization of the public sector in Slovenia and the measures in place aiming to increase user-friendliness of the services offered, while the purpose of the practical research work conducted was to analyze current data on customer satisfaction at the Krško Administrative Unit. The goals of the thesis were to define state administration quality management systems, define methods of quality measurement, define the concept and importance of customer satisfaction, and to determine the level of customer satisfaction. The aim was also to determine whether the customers of the Krško Administrative Unit are satisfied with the office hours and which services they are satisfied with most. The thesis provides an understanding and an overview of the current state of affairs in the customer satisfaction area with an administrative unit, whilst providing an outline of the measures implemented so far as well as developing ideas for improvement. The results show that the majority of customers are very satisfied with the work of the Krško Administrative Unit, and that there is no increase in use of administrative unit’s e-commerce platform. The hypothesis that customers are satisfied with the established office hours was also confirmed. Thesis findings can therefore benefit both, the administrative unit management and its employees, as customer satisfaction can be further increased by implementing certain measures, therefore, consequently improving the efficiency and effectiveness of the organization.