Symptoms and functional limitations are commonly reported primary outcome measures in ankylosing spondylitis (AS); however, participation has not been widely evaluated, as reflected by the scarcity of literature on the subject. People with AS suggest that participation in social roles (e.g. employment, leisure, and relationships with others) is a critical outcome that is often adversely affected by the sequelae of the disease and by the demands of managing them. Confusion surrounding the concept of 'social role participation' has presented difficulties in defining, developing and using participation as an outcome measure. Specifically, distinguishing participation in a social role from the performance of activities that might be associated with that role is critical for measuring participation, as the repertoire of associated activities will vary between individuals. Furthermore, considering which roles are important to individuals and evaluating their satisfaction with participating in a role at the times and in the ways they would like are also key elements of this measurement. Participation as an outcome measure takes on increased importance in diseases such as AS where, in the absence of a cure, the benefits of interventions often arise from improvements to patients' quality of life. Participation is a predictor of quality of life in diseases other than AS; therefore, evaluating social role participation, understanding the factors that affect it, and intervening to prevent or alleviate participation restrictions will be critical for people with AS.