Floods are highly relevant extreme events with increasing frequency at a global scale. They remain among the most dangerous and complex natural disasters in middle and low-income countries. In this context, it is necessary to develop decision-support tools to reduce the flood risk and increase the resilience. The chapter reviews one of the most relevant tools, the flood vulnerability index (FVI) category at a global scale. These tools use hydrological, topographic, socio-economic parameters strongly associated with flood vulnerability. The findings indicate that FVI is a flexible tool for integrated assessment of vulnerability to floods for application in different regions. Social, environmental, and physical components are the main components used in the FVI. Household and neighborhood, basin, urban, sub-catchment, and coastal are the different levels of vulnerability analysis.