Readers of older multi-volume editions of Shakespeare, such as the Arden (which has now almost completed its third series and has already announced a fourth), will remember that a substantial section of the introduction was always devoted to sources, understood as previous works to which Shakespeare was indebted for details of plot and characterization, and for verbal borrowings. A glance at more recent volumes will reveal that such details are now dispersed among other material and that editors have become reluctant to write about sources in this way. The high-water mark of the old tradition was Geoffrey Bullough’s Narrative and Dramatic Sources of Shakespeare, published in eight volumes between 1957 and 1975 and still a standard reference work. Bullough carefully distinguished between “source,” “probable source,” “possible source,” and “analogue,” and his scrupulously detailed commentaries aimed to make it possible to see, as he put it, “Shakespeare the craftsman in his workshop.” Ironically, as John Kerrigan notes in his new book Shakespeare’s Originality, Bullough brought his labors to an end just as new critical fashions were making source study seem outmoded or even futile. The author was officially declared dead, and “intertextuality” was all the rage. Kerrigan is not wholly hostile to intertextuality, but he grants that it “did more for Joyce studies than it ever did for Shakespeare criticism.” His own approach is very broad (the text of the book runs to just over a hundred pages but the notes reveal that it is based on