When a butterfly is pinned to card and put on display in a case, the scientist whose objective is to study the creature is able to measure it, photograph it, describe its colours, document its features in order to describe how they probably function, and admire its evolution and its uniqueness. It is still dead, however. Before its demise the butterfly flew unpredictably from flower to flower, fed and bred, interacted with its world and seemed impossible to pin down, to study with precision and to comprehend fully, however beautiful its appearance and admirable its function. If a fleeting but visceral sense of awed impotence accompanies the scientist's observation of the butterfly in flight, it is akin to the rich experience of seeing and hearing a page-bound play-text come to life on the stage. For the observer in the audience there is a feeling of incapacity, an awareness that the whole performance cannot be recalled and recorded faithfully, but an exhilaration at the fullness of the experience. This is what happens when the words on the page take flight, when they do what they were written to do. For the text-based academic scholar this moment is also one of anxiety, as measurements painstakingly taken might appear to be otiose when the text comes to multi-dimensional life.

The study of plays in performance – and indeed the recognition that it is important to study drama as theatre – has arrived comparatively recently in the academy. After the awakening of interest in specific performances, often of Shakespeare plays, in the 1960s (for example in John Russell Brown’s Shakespeare's Plays in Performance), came works, notably semiotic studies, that attempted to theorize and anatomize performance, to turn such study into a science. Nowadays no serious critical edition of a play by Shakespeare or his contemporaries is published without a consideration of its performance (history), and, however elusive and ephemeral performance may be, whatever the problems surrounding its analysis, its study is seen as essential to a rounded understanding of the play. The possibilities of multi-media publications for the study of drama in schools and universities in an age dominated by the visual will no doubt ensure that studies based on performance continue to thrive into the future.