This doctoral project was born of the hypothesis that where playwrights have succeeded as film directors, it has been as a result of building on those qualities which make them effective as authors within theatre. After establishing the existence of a substantial body of work by a variety of playwright-filmmakers, I reviewed the literature examining the relationship between theatre and film; then critically assessed the status of the author within film theory, prior to analysing the work of selected playwright-filmmakers (Preston Sturges, David Mamet, Rainer Werner Fassbinder and Neil LaBute), attempting to isolate those aspects of their practice which are attributable to their experience as dramatists. Parallel to this, I attempted to develop a theoretical practice based on what I discovered; a process involving the development of a “Dogme”-style manifesto, and the production of three short films. I conclude with a discussion of the extent to which every playwright might be considered a potential filmmaker. This book will be of particular value to those with an academic or practical interest in the interface between film and theatre.