Urbanization is the process through which people migrate from rural to urban areas, leading to the expansion of towns and cities. It involves the growth of populations in urban centers and the transformation of these spaces into hubs of economic, social, and cultural activity. Historically, urbanization has been linked with industrialization, as cities provided opportunities for employment, education, and access to services that were unavailable in rural regions. In modern times, urbanization has accelerated on an unprecedented scale, particularly in developing countries, creating both opportunities and challenges for governments and societies. While urbanization is often considered a driver of economic development and modernization, it also brings forward a series of social, economic, environmental, and infrastructural issues that require careful planning and management, particularly in the context of sustainable development and the vision of building smart cities. One of the primary issues of urbanization is the pressure it exerts on housing. Rapid migration into cities often exceeds the ability of urban authorities to provide adequate housing facilities, resulting in the growth of informal settlements and slums. These areas frequently lack access to safe water, sanitation, and waste management, creating unhygienic living conditions that contribute to disease and poor health outcomes. Affordable housing becomes scarce, and real estate prices skyrocket, pushing vulnerable populations further into poverty. Addressing this challenge requires innovative housing policies, sustainable building practices, and inclusive urban planning that ensures access to dignified living conditions for all residents. Another pressing challenge is the strain on urban infrastructure. Cities face enormous pressure to expand transportation networks, water supply systems, sewage treatment facilities, and energy grids. However, in many cases, infrastructure development lags behind population growth, resulting in congestion, inadequate public transport, frequent power shortages, and water scarcity. This imbalance undermines the quality of life for urban dwellers and hinders the efficiency of economic activities. Smart city solutions such as intelligent traffic management, integrated public transportation systems, and renewable energy grids can mitigate these issues if implemented with foresight and inclusivity. Environmental degradation is also a significant challenge associated with urbanization. Cities are responsible for a large proportion of global carbon emissions due to industrial activity, high energy consumption, and increased vehicular traffic. Urban sprawl often leads to deforestation, loss of agricultural land, and encroachment on natural ecosystems. Air and water pollution rise as cities expand, posing risks to both the environment and human health. Furthermore, the generation of massive quantities of solid waste overwhelms municipal capacities for collection and disposal. Sustainable urban planning calls for eco-friendly technologies, green building designs, and circular economy practices to reduce environmental footprints and build cities that coexist harmoniously with nature. Social inequality is another complex issue tied to urbanization. Cities attract diverse populations from different economic and cultural backgrounds, but