The aim is to explore the perception of being a support person for clients with acquired brain injury undergoing vocational rehabilitation. Nine support persons, identified by clients with brain injury, were interviewed. Interviews were analyzed using qualitative content analysis, resulting in three themes for assisting the client: (i) commitment; (ii) adaptation; and (iii) cooperation. Within each theme, multiple dimensions were identified, reflecting the complexity of vocational rehabilitation following acquired brain injury. Commitment built on social relations is linked to sustainability of support. The included support persons' role was especially valuable in contexts where adaptation and cooperation were required.