''Cities are hubs for ideas, commerce, culture, science, productivity, social, human and economic development. Urban planning, transport systems, water, sanitation, waste management, disaster risk reduction, access to information, education and capacity-building are all relevant issues to sustainable urban development.'' https://sustainabledevelopment.un.org/topics/sustainablecities. 

The concept and introcution of ' Liveable Cities',  by Agenda 21, the Rio Declaration on Environment and Development. Many cities have adopted and put their effort to make their duellers live safely and breath well. Several experiences have been documented and shared for kneighbouring cities and towns. Hence, in this issue, many of the national and global experiecnes are case studied and made public reports. So, openly, scholars are invited to contribute to the society.