Cities represent artificial environments created by humans, fundamentally distinct from natural settings such as seas or mountains. However, unlike mass-produced industrial products such as automobiles or cameras, cities are extensive, artificial environments unique to their regions, shaped over decades, centuries, or even millennia. This chapter discussed disasters in modern cities, which have evolved into highly complex systems, and illustrated the relationship between urban disaster risk and the components of hazard, vulnerability, and exposure using a simplified mechanism of urban disaster occurrence. Additionally, the concept of the Disaster Life Cycle was introduced to explain two pre-disaster strategies: Mitigation and Preparedness. Mitigation is an action to reduce the loss of life and property by lessening the impact of disasters. Preparedness involves measures designed to minimize damage through lifesaving and rescue activities during an imminent crisis or after a disaster has occurred. Striking a balance between these approaches is crucial for achieving a resilient society. Finally, the chapter highlighted the significance of disaster damage estimation and emphasized the necessity of developing effective Regional Disaster Management Plans based on such estimations.