Introduction. We focused on older persons with disabilities and studied their aging and social participation trajectories in five regions of Chile. The objective was to understand the factors that influence the social participation of this population group. Social participation is a key issue in aging discourse whether in scientific, political, or media-based narratives. Yet conditions of access to participatory opportunities are rarely problematised. While a homogenising perspective on old age has prevailed in Latin America and the Caribbean, an emerging theme is the diversity of older people. Methodology. . The work focused on the intersection of old age and disability, seeking to unravel the personal and environmental (social and physical) factors underlying the social participation of older persons with disabilities. Biographical accounts of 17 older people were analysed, as well as the professional experience of 11 key informants working in the disability sector, in public or community organisations. The Human Development Model - Disability Creation Process was used as a theoretical construct to reveal how the interaction between individual factors and their relational, organisational, and structural contexts can contribute to the participation of people with disabilities or, conversely, to their social exclusion. Results. Regarding personal factors, three main themes were notable: disability trajectory, mental health, and self-determination and the use of technical aids. In terms of environmental aspects, three topics emerged: social networks, environment accessibility, and discriminatory discourses. Although the interviewees faced social participation obstacles, they also exercised their agency and self-determination, deploying strategies that reinforced their autonomy. Discussion. With respect to personal factors, their individual disability trajectories varied widely. This fact, added to their respective identities and preferences, contributed to making their participatory practices unique. Older participants had in common an individual responsibility to tackle social participation barriers and did so with incentive and agency. In terms of environmental factors, institutional services and support were inadequate, making the presence and support of relatives essential to overcome various mobility and activity obstacles. Yet, participants also verbalised the following: that they felt they were a burden for their network members; they were infantilised and overprotected; and that their greatest fear was losing their autonomy. Conclusions. It is critical to continue building knowledge on the realities of older persons with disabilities and to identify possible measures to promote their participation in society, particularly regarding public policy and universal accessibility. To drive disability cultural change, it is important to shed light on the main sources of exclusion as well as community accountability.