Barcelona and Osaka are also well known for doing a good job at facing the challenges of developing a big city. Nagoya and Taipei have been mentioned to me as e

Barcelona and Osaka are also well known for doing a good job at facing the challenges of developing a big city. Nagoya and Taipei have been mentioned to me as examples, too. Mexico City deals every day with the challenges of having grown very fast to 20 million before it became rich. New subway and BRT lines, infill development, upgrading properties, and progressive transit and construction planning keep the place getting better to live in and easier to get around every year. Phasing in pollution and emission regulations as they became affordable and regulating polluting industries out of the region step by step worked well, too. In spite of the famous chaos of Mexican government, Mexico City will soon mark thirty years of effective governance and planning, so it can be done. If Mexico can do it, China and the USA -- which are usually considered to be only somewhat worse governed than México -- could probably do it, too, someday.