BACKGROUND: Family member engagement is increasingly recognised as an influential factor in the rehabilitation continuum following Acquired Brain Injury, including the inpatient setting and longer-term community integration phases. OBJECTIVE: To explore the experiences of patients and family members about their involvement in brain injury rehabilitation. METHODS: This study comprised individual and group interviews with 14 ex-patients and family members. Interviews explored effects of inpatient rehabilitation on family relationships. Interview audio recordings were analysed using an interpretive approach by two independent researchers. RESULTS: Findings clearly confirmed the significance of engaging family members in inpatient rehabilitation, and specifically reinforced the importance of informational, emotional, practical and peer support. However, the key finding of the study was the importance of hope, and the need for rehabilitation professionals to foster hope. Despite not having included any questions on this topic, all interviewees noted the importance of hope, some saw it as fundamental to positive outcomes, and many were unconvinced of rehabilitation professionals' concern to avoid false hope. Various dimensions of hope are explored. CONCLUSIONS: The study notes that hope has been identified as highly important in many areas beyond brain injury rehabilitation. Based on this small preliminary study, the issue of hope is seen as a key focus for future research.