This paper examines the evidence for community and outpatient aphasia groups using the International Classification of Functioning, Disability and Health (ICF) framework. A systematic search of the literature using eight electronic databases was completed; 29 studies met inclusion and exclusion criteria. Level of evidence and methodological quality was assessed and effect sizes calculated where possible. Evidence favouring community and outpatient groups centred on four level ii and level iii-i studies that examined the efficacy of highly structured group activities for improving specific linguistic processes with five medium-large effect sizes calculated. Medium and large effect sizes were also calculated on a level iii-i study examining number of friendships and community access. No effect sizes were available for level ii or level iii studies examining communication activity and participation. Overall, the results indicate that community and outpatient group participation can improve specific linguistic processes. There is also some evidence that group participation can benefit social networks and community access. However, there is limited evidence demonstrating improvement in functional communication as a consequence of group participation. The current evidence is not comprehensive. Further well-designed studies, particularly examining activity and participation, and contextual factors are required to advance community and outpatient aphasia group practice and participation.