The English System is a history of port health and immigration at a critical moment of transformation at the end of the nineteenth and beginning of the twentieth century. It challenges generally held assumptions that quarantine policies delineated intransigent national borders, and argues instead that the British geo-body was defined as a more fluid construction. A combination of port sanitation and sanitary surveillance, known to contemporaries as the 'English System', was gradually introduced as an alternative to obstructive quarantines at a time of growing international commerce. Yet at the same time escalating anti-alien anxieties sought to restrict the movement of migrants and transmigrants who arrived from the Continent in increasing numbers. With the abolition of quarantine in 1896, the importance of disease categories based on place, which had formed its foundation and which had been adapted for the new 'English System,' lessened. However, these categories had not collapsed but were merely transferred. This book examines this crucial transition showing how the classification of 'foreign' and 'domestic' disease was translated, after the abolition of quarantine and during the period of mass migration, to 'foreign' and 'domestic' bodies - or the immigrant and the native population. It will be essential reading for any student or scholar of the history of medicine and public health in Britain or North America.