With built public utilities the lands obtain useful value and the ability to build certain types of facilities on them. With that formative function, public utility development is a significant impact on the development of activities in the area, taking into account the paradigm of sustainable development. In Slovenia the law that governs the spatial planning associates the concept of sustainable development with the rational use of space. The principal objective of the diploma is, basing on the analysis of developed urban land in the Municipality of Kranj, to evaluate the implementation of the rational use of space in the terms of sustainable spatial development. The first part presents the basic theoretical bases and concepts of sustainable spatial development of settlements, which are expected in the spatial policy documents at the national and local level. In the central part of the diploma the situation and processes in the spatial development of the city of Kranj in the case of the existing residential neighborhoods of organized construction are discussed on the basis of available data. The convergence of human activities in the space to the theoretically outlined guidelines is established through the indicators of the spatial planning and the public utility development. These indicative indicators can serve as the basis for the optimal (physical) planning of public utilities in a new land. Therefore, at the end of the diploma the fundamental advantages of the presented indicators are emphasized, their defectiveness is pointed out and possible measures for the effective implementation of the policy of sustainable spatial development in the lands of the public utility development are provided.