 Visiting positions include UCLA, Auckland and Princeton.During the 1980s Kerrigan established himself as one of a group of scholars who revolutionised the editing of Shakespeare by discrediting the practice of 'conflating' variant early texts of such plays as "Hamlet" and "King Lear", though his position, like that of others, has become more complicated over time.His own editions include "Love's Labour's Lost" (1982) and Shakespeare's "Sonnets and A Lover's Complaint" (1986).