That a large number of Elizabethan plays are the product of dramatic collaboration is well known. Just how this process of ‘collective creation’ operated in the public theatres, however, remains something of a mystery. Attempts to explore the mechanics of collaborative play writing have been of different kinds. The most common have been studies of published plays undertaken in the hope that characteristics of style would reveal the shares of contributing dramatists. In spite of valuable work (notably by Cyrus Hoy), however, too many of these studies suffer from the weaknesses described by Samuel Schoenbaum in his analysis of the limitations of conclusions about authorship based on internal evidence. As a consequence, assertions about patterns of collaboration based on the identification of an author's stylistic characteristics, such as those made in the early 19205 by Dugdale Sykes, are not as fashionable as they once were.