This unique reference guide provides descriptions and evaluations of archive manuscript materials and ephemera relating to twentieth-century British and American theatre. Over 100 archives across Europe, North America and Britain were examined in the compilation of this volume. The documents include: unpublished playscripts; state and costume designs; directors' books; prompt books; lighting plots; stage photos; correspondence; theatre programmes. One hundred and seventy five entries are arranged alphabetically and cover playwrights, directors, designers and actors. By its nature, theatre is a collaborative enterprise, a facet which is recognised in the comprehensive cross-referencing of entries. The last twenty years has seen a shift in drama studies from text-based criticism to analysis of performance. The materials covered in this book have therefore become essential to future research in the field.