London’s seasonal foreign trade reflected its access to northern and continental Europe and the City’s association with the East and West Indies, but coal and other coastal trades dominated daily port activity. London was a tidal river port centred below London Bridge, with waterfront industry spread more widely. Organisationally, it was complex, with many different interests. As foreign trade increased, legal restrictions on landing places for foreign produce were blamed by merchants for congestion. A campaign by mercantile interests for the introduction of docks followed. The author examines the motives here. For leading West India merchants, specialised dock facilities would enable them to control and discipline a directly employed labour force, reducing theft. The eventual outcome, the construction of docks by joint-stock companies, owed much to State support. Its involvement went beyond the introduction of docks. For the government, this was an element of a warehousing scheme designed to develop London as an entrepôt. General port efficiency would be promoted by appointing the Corporation of London as harbour authority.