Objective: To investigate the participation outcomes of individuals with severe acquired brain injury (ABI) who were provided with up to 12 months of intervention based on the Community Approach to Participation (CAP). Method: A case series study design was undertaken with a total of 85 participants from two private practices specialising in community-based, CAP rehabilitation for people with severe ABI. Inclusion criteria were the person had sustained an acquired brain injury, was aged over 18 years and had received up to 12 consecutive months of CAP input from one of the two practices within a three-year period between January 2004 and January 2007. Twenty-six of the 85 participants were an average of 343 days post injury (Early group) and 59 of the participants were an average of 10.2 years post injury (Late group). They were living in a range of community environments and residential facilities. Initial participants were identified for the study in January 2005. Data were gathered using the Functional Independence Measure (FIM™), Community Integration Questionnaire (CIQ), and Role Checklist (RC Part 1) at two time points: prior to intervention (baseline), and after a 12-month period or at discharge (TI). Within the intervention period, all participants received a customised community occupational therapy (OT) rehabilitation program based on the key principles of the CAP. Intervention focused on participation goals of the individual, and development of the associated skills that underpinned valued role performance. Results: Participants each received an average of 51.01 hours of CAP OT during the 12-month period of intervention. Considerable improvement was seen in functional independence, community integration, and role participation after intervention in both the Early and Late groups. A statistically significant increase in FIM™ and CIQ total scores was found for all participants from Baseline to T1. The number of roles in which participants engaged increased on average by almost one role per participant following intervention, from a mean of 3.06 to 3.99. Increased participation in volunteer, home maintainer, participant in organisations and hobbyist roles were most common. Conclusion: Increased functional independence, community integration, and participation in both the Early and Late groups over a 12 month period demonstrates the potential for improved participation outcomes for people with complex needs following ABI, even many years post injury.