Thesis advisor: Stephen J. Pope / This dissertation attends to the crisis of addiction in the United States. The increasing number in annual overdoses and the inadequacy of national responses to curtail these preventable deaths demands an immediate moral response. In the last year, deaths caused by overdose increased by nearly 29 percent, and 20.8 million people in the United States are currently living with substance use disorders. The number of families affected by addiction presents a striking testimony to the scope of the problem. Nevertheless, there is still enormous disagreement over the nature of addiction and therefore how to best treat it. This dissertation will therefore offer a theological approach to addiction in order to advocate for a social response to this crisis.This dissertation proceeds in five chapters. In the first chapter, I evaluate the medical and moral models of addiction. This first chapter engages research in neurobiology and psychology and argues that these models are premised upon a false dichotomy between determinism and freedom of the will. The second chapter explores disagreements in bioethics over the meanings of health, disease, and illness. These different definitions contribute to the chasm between the medical and moral models of addiction. This chapter proposes a holistic account of health for understanding addiction and healing. The third chapter grounds this holistic account of health in Karl Rahner’s transcendental anthropology in order to uphold the fundamental relationality of human persons and to move past the false dichotomy presented in chapter one between determinism and freedom of the will. This chapter then offers a theological examination of sin as a power or force that preconditions freedom. It concludes by proposing a theological and relational account of autonomy. The fourth chapter engages philosophy of the mind in order to argue for a nonreductive approach to mentality that appreciates the ways in which human persons are co-constituted by bottom up and top down causality. A nonreductive approach to mentality offers a way to understand addiction as an interacting set of processes and patterns. This fourth chapter concludes by considering the possibility for responsibility by examining narrativity, vulnerability, and imagination. It argues that there is a moral responsibility to imagine a better world for people living with addictions, and to bring that world about. Finally, the fifth chapter draws upon the theological virtue of solidarity and the principle of the preferential option for the poor in order to articulate a preferential option for people living with addictions. I argue here that Church institutions can stand in solidarity with people who suffer from addiction by acting as providers, educators, and lobbyers. / Thesis (PhD) — Boston College, 2022. / Submitted to: Boston College. Graduate School of Arts and Sciences. / Discipline: Theology.