This dissertation argues that there is a dogmatic or doctrinal structure to the theology of Bonhoeffer's doctoral dissertation Sanctorum Communio. It argues that this dogmatic structure is crucial for understanding Bonhoeffer's engagement with social theory and his account of the church.  Chapter One argues that Bonhoeffer develops a distinctive ecclesiological approach to theology as a response to both Ernst Troeltsch's historicism and Karl Barth's dialectical theology. Against Troeltsch and Barth, Bonhoeffer understands the church as both revelational and as a fully human, social entity.  Chapter Two examines how Bonhoeffer sets up this theological engagement with social theory. It explores the central methodological distinctions he makes between historical and formal approaches to sociology, and between social-philosophy and sociology. This chapter also examines how Bonhoeffer carefully situates his engagement with social theory as a critique of the social-philosophy of idealism. Bonhoeffer develops a 'theological narrative' or 'conception of reality' that contests the idealist understanding of reality (i.e., the progressive unfolding or realization of spirit in history). Chapters Three and Four develop my claim that Bonhoeffer's engagement with social theory is structured by this 'theological narrative' or 'concept of reality.' Chapter Three explores how Bonhoeffer uses the doctrine of creation as a basis for appropriating from existing social theory, and for developing his own 'specifically Christian social-philosophy and sociology.' Chapter Four explores how he then fundamentally reworks this Christian social theory in light of the new situation of sin. In both these chapters, Bonhoeffer gives priority to narrative or concept of reality as intrinsically broken over insights and concepts from social theory. Chapter Five argues that Bonhoeffer's theological engagement with social theory (in the earlier chapters of Sanctorum Communio) is integral to Bonhoeffer's account of the church. In Chapter Five, I argue that many of Bonhoeffer's central theological formulations' e.g., 'vicarious representative action' and 'Christ existing as community'' are only fully comprehensible in relation his Christian social philosophy. I also argue that Bonhoeffer's analysis of the church as its own unique sociological type only makes sense when viewed in relation to his specifically Christian sociology. This dissertation concludes by reflecting on the implications of the theology of Sanctorum Communio for recent scholarship in theology and Christian ethics. In particular, I address some of the implications of Sanctorum Communio in relation to scholarship that has given emphasis to the visible distinctiveness of the church.