Urbanization is rapidly increasing worldwide, including in developing countries. Rapid urbanization presents significant challenges, such as unemployment, poverty, inadequate infrastructure, and environmental degradation in many developing country cities. Over half the world's population now lives in urban areas, crowded into just 3% of the Earth's land. By 2030, 65% of the global population is expected to be urbanized. Effective urban planning, infrastructure development, and management are needed to address the problems caused by rapid urban population growth and density in cities.