The year 2013 marks the fiftieth anniversary of the publication of Irfan Habib's The Agrarian System of Mughal India. The book was a revised and enlarged version of a D. Phil. thesis submitted in 1958 at the University of Oxford, where the author had gone on a Government of India scholarship from 1955 to 1958. This Special Essay reviews and analyses the main features of a book that remains a landmark, and which, upon publication, struck even its critics as being singular in a seemingly well-worn field.