To understand how the spouses of individuals with severe TBI experience the process of supporting their partners with decision-making.This study adopted a constructivist grounded theory approach, with data consisting of in-depth interviews conducted with spouses over a 12-month period. Data were analysed through an iterative process of open and focused coding, identification of emergent categories and exploration of relationships between categories.Participants were four spouses of individuals with severe TBI (with moderate-severe disability). Spouses had shared committed relationships (marriage or domestic partnerships) for at least 4 years at initial interview. Three spouses were in relationships that had commenced following injury.Two main themes emerged from the data. The first identified the saliency of the relational space in which decision-making took place. The second revealed the complex nature of decision-making within the spousal relationship.Spouses experience decision-making as a complex multi-stage process underpinned by a number of relational factors. Increased understanding of this process can guide health professionals in their provision of support for couples in exploring decision-making participation after injury.