Megacities in developing countries suffer from serious traffic congestion, high levels of greenhouse gas (GHG) emissions, and heavy air pollution. These urban areas face a stark dilemma: economic expansion attracts more people and vehicles
but the resulting traffic and pollution hinder further growth while reducing the quality of life for their citizens. Not long ago, Seoul faced a similar conundrum. Choked with pollution and traffic jams, it changed course and helped Korea make a historic transition to green urban transport. It shifted from supply-side policies focused on expanding roadways and metro lines to green demand-side policies focused on creating transit-oriented cities. Today, Seoul boasts a passenger-trip share for metro and bus of more than 60 percent. Energy consumption in Korea's road sector is lower than in other countries with similar gross domestic product (GDP). Congestion costs have been decreasing, and carbon dioxide (CO2) emissions in the transport sector have been kept under control. This path breaking transition was founded on multimodal solutions integrated by information and communication technology (ICT) in a context of strong political leadership and public financing.