Flooding is the most frequent natural hazard of all weather-related disasters and generates about a third of all economic losses due to natural hazards worldwide. Coasts are particularly vulnerable areas due to their rising population and wealth. These dynamic areas are exposed to different sources of flooding, driven by the interaction of oceanographic, hydrological, geological and meteorological processes, for example fluvial, coastal, pluvial, and groundwater floods. This thesis focuses on the interactions between fluvial and coastal floods. Global flood risk assessments currently consider either riverine flood risk or coastal flood risk only, neglecting interactions between the two; floods of this type are known as compound – fluvial and coastal – flooding. If these joint occurrences are not properly modelled, they are also not accounted for in flood hazard assessments and may result in an underestimation of the risk. This PhD thesis aims to address the latter by quantifying the probability of the joint occurrence of coastal and river floods along the global coastline.