There are over 30 megacities with populations of 10 million or more, expected to increase to 41 by 2030. These cities have the potential to become smart and global if planned sustainably. The book discusses case studies of megacities and how they can be transformed into smart global cities. Factors like population diversity, cultural richness, and global connections make these cities ripe for transformation. The chapter explores the growth and development of these cities across different regions, and proposes strategies to make them smart and global. The economic community design strategy has been successfully implemented in the Kochi-Kannur megacity study.