The central research inquiry of this dissertation is how the experience of working within a collaborative context, employing the processes of devising, affects a playwright. It springs from the presentiment that the processes of devising are significantly different than traditional playwriting methodologies and have the potential to offer short and long-term benefits to both playwright and collaborators. A central focus of the dissertation is the figure of the writer-deviser as a distinctive artist with a particular skillset developed from both devising praxis and standard playwright training (which traditionally does not emphasise collaborative theatre-making). This dissertation therefore examines the historical and contemporary context of the writer-deviser in order to provide a foundation for the presentation and exegesis of my practice-as-research: a play written via the devising process and another play written as a solo playwright. The Introduction to this dissertation serves the function of presenting the central research query and associated areas for exploration. It outlines my methodological approach, placing it within the context of the discourse on performance-related practice-as-research, whilst identifying a gap within this discourse of the treatment of the playwright. Chapter One presents an overview of devising in its historical and contemporary context. The chapter also functions to identify positive aspects of devising which may aid a playwright’s development, and, alternatively, pinpoint problematic issues associated with devising. Chapter Two provides an overview of pedagogical approaches to playwright development. Original research is presented via a playwrights’ survey on training and experiences of devising. Pedagogical approaches which may aid the writer-deviser are identified, and areas of weakness revealed. Chapter Three defines the concept of the writer-deviser, incorporating challenges to the dramatic/postdramatic and text/performance binaries. This is achieved through commentary on historical and contemporary examples of writers working in a collaborative context. Chapter Four further develops the figure of the writer-deviser through a case study of Bryony Lavery, providing a close analysis of two scripts created using devising methodology, and one written as a solo playwright. Chapter Five presents the exegesis of practice-as-research section of this dissertation, with reference to the devised play The 9.21 to Shrub Hill and the non-devised play Playground, which are presented in a section entitled ‘Playscripts’. An outline of the process of both productions is provided, linked closely to the discourse of the preceding chapters of this dissertation. Based on a comparison of the two processes, findings are revealed and suggestions for other writer-deviser practitioners and devising companies are presented in a Toolkit. The conclusion reflects on the argument of the dissertation and its realization within the playscripts, and highlights areas for further investigation.