the process of achieving to sustainable cities

subsequent to the concept of (urban) sustainable development, urban planners have turned to the attainment of development of sustainable cities in the last two decades and they have made extensive studies in this regard. making use of the concept of 'process' in attaining to sustainable cities within the framework of urban development projects is regarded as one of the viewpoints whose necessity was appreciated in the last century and as a consequence, various processes were discussed. the present discussion is an attempt to survey the development of the concept of sustainable urban planning and review a number of discussed processes and their analyses in order to present a general and comprehensive process of attaining to sustainable cities. considering the significance of the concept of assessment in the suggested process as three significant steps in the above process, the position and methodology of assessment in the process of attaining to sustainable cities are also expounded.