This thesis attempts to highlight in a new way the importance of work to Dietrich Bonhoeffer, both in what he wrote and how he lived, and draws upon history, biography, and theology. It constructs a narrative drawn from the interrelation between these elements in an innovative fashion, seeking to convey a fresh sense of the way in which Bonhoeffer’s theology relates to the context of the time. A central argument of the study is that Bonhoeffer’s engagement with the subject of work and his theology of work is something foundationally important to him and a theme which evolves and develops over time. Proposing work as a central hermeneutical key to the understanding of Bonhoeffer is a task which has not been attempted before. The thesis tracks the theme of work and its development, noting over the course of Bonhoeffer’s life how a fuller understanding of the centrality of work throws up fresh understandings of a number of key transition points in his life and makes sense of them in a new way. The final section argues that Bonhoeffer’s work in resistance in Nazi Germany was good work and that a theological formulation which guided Bonhoeffer towards his role in tyrannicide was present in his work-in-progress doctrine of the mandates, an incomplete doctrine which in the end is a hope-filled one. Methodologically, this thesis tracks the development and articulation of Bonhoeffer’s theology of work from the early days through to his arrest, focussing mainly, but not entirely, on his written output in the Dietrich Bonhoeffer Werke (DBW) series, but not including the prison theology because such an approach appropriately reflects the un-finished nature of Bonhoeffer’s theology.