Paleohydrology is defined as the study of fluvial processes and their hydrological implications before the onset of instrumental records. Key challenges in fluvial paleohydrology include quantifying the response to global change of: runoff and discharge regime; sediment transport and storage; and extreme floods. Recent technological advances now enable the quantification and integration of sediment and flow regime data over a range of spatial and temporal scales that allows the potential for various allogenic and autogenic processes to be deciphered in alluvial sedimentary archives, in particular through combined stratigraphic and modeling approaches.