In many cities around the world, including Zagreb, it is necessary to implement the principles of urban sustainability in urban development in order to reduce the harmful impact on the environment and to ensure the quality of life of the urban population. Given that there is not much research on this topic, especially not specifically for Zagreb, the focus of this paper was to use several methods to explore the current situation related to 2 elements of urban sustainability - sustainable transport and public green spaces. The spatial analysis determined the current situation, and the results of the survey and interviews revealed what young people as a future experts and actual experts in relevant fields think about it and how this situation affects their quality of life and the quality of life of residents in general. The results of spatial analysis show that large green areas such as Maksimir or Sljeme are no longer sufficient for the needs of the city, and spatial planning only reduces the share of green areas in urban space. Also, although more and more seems to be invested in sustainable forms of transport, cycling infrastructure and the quality of public urban transport are not of sufficient quality to encourage more intensive use of these forms of transport. These findings are confirmed by the results of the survey and interviews. Young people and experts agree that the City of Zagreb does not pay enough attention to sustainability in general when planning and point out that ultimately all of the above has a negative impact on the quality of life of the inhabitants of the city of Zagreb. It is necessary to make better use of all the spatial potentials of Zagreb and when planning pay more attention to the requirements of the population and the principles of sustainability.