This research paper intends to show the evolution of sustainability concepts and the emerging direction to Sustainable Architecture and Urbanism. The purpose of the study takes into consideration cases studies based on literature review about important architects and theorists all over the World in order to select the basic principles of sustainable urban development defined in the Agenda XXI. The research methodology is based on cases studies as referred by Robert Yin principles. The results show that sustainability is one possible direction defined for Architecture and Urbanism as a response to solve the needs for future generations. The conclusions evidence how Sustainable Architecture and Urbanism should stand for a basic integrative attitude to introduce in all levels of the Architectural and Urbanism Process in order to purse sustainable development.