Due to the change of the city form in terms of density of buildings, urban sprawl and the negative effects of urban activities on the surrounding environment, it becomes very important to raise the awareness of urban designers regarding the concept of sustainability and how it can be used to achieve integrated urban design. Accordingly, the concept of sustainability will be applied on not only buildings but also on urban spaces by using a comprehensive approach which produces qualitative and integrated urban spaces. The trend of achieving sustainable urban spaces represents one of the latest phases of urban design which aims to face the current challenges in terms of climate change, shortage of water and energy resources and increasing consumption of the available materials. However urban design considers the criteria of permanence and continuity, it is crucial to focus on the advantages which can be added to urban areas when the dimensions of sustainability are considered. The research problem is the focus on achieving sustainability in buildings and ignoring this aim at the level of urban spaces although the criteria of sustainable site is required in many local and international rating systems of sustainable projects. Additionally, most research studies focus on the strategies and techniques of achieving the environmental sustainability without taking in account the economic and social dimensions of sustainable urban design. This research aims to clarify and analyze the aspects of sustainability in urban design at the conceptual and practical levels in order to determine the aims and principles which are added by the sustainable approach of urban aspects of sustainability in urban design at the conceptual and practical levels in order to determine the aims and principles which are added by the sustainable approach such as protection of the bio-diversity, development of strong economy which does not consumes the natural resources through many techniques that utilize the available opportunities and possibilities, ensure the justice of services distribution, consider different ages of users and express the local culture and the social context. Finally, King Abdallah University for Science and Technology (KAUST) has been analyzed as an example of sustainable urban spaces.