The maritime legal framework of General Average (GA) remains an enigmatic and overlooked process within the history of seaborne trade. An ancient rule that redates Roman Law, it continues to be operational today, in a largely unchanged state, mandating the redistribution of unexpected costs that arise during a maritime expedition amongst shipowners and merchants. In this detailed examination of Average procedures within the Italian maritime republic of Genoa, between the years 1590 and 1700, Through the Water and the Storm demonstrates how this rich data can be used to investigate the dynamics of Mediterranean seaborne trade.