This paper looks at why businesses and people tend to gather in big cities in Indonesia and the Philippines. They studied how bigger groups of companies and consumers in these urban areas can bring benefits. The study found that companies making goods benefit from being close to each other (localization), while service providers like shops thrive from being in crowded places (urbanization). The research supports previous ideas about why businesses and people prefer living in bustling cities rather than smaller towns. The study also gives advice on how countries can use this information to make better decisions for economic growth.