Greg's theory of copy-text and the editing of American literature, 1950-1974
Recent editorial discussion and the central questions of editing, 1974-1979
Historicism and critical editing, 1979-1985
Textual criticism and literary sociology, 1985-1990
Textual instability and editorial idealism, 1990-1995
Textual criticism at the millennium, 1995-2000.