Background : People with intellectual disabilities who live in residential facilities may need social support to express self determination. Relationships with social care professionals provide an important context for promoting self-determination. Adopting a socioecological perspective, our study aimed to better understand the nature of these relationships. Method : Over a period of ten months, we held 13 focus group discussions with a total of 20 participants, including both residents and staff at facilities for people with intellectual disabilities. Using transcripts of these discussions, we analysed expressions of self-determination among people with intellectual disabilities and the responses of social care professionals. Results : Our results highlight the importance of relational adjustment in fostering self-determination among people with intellectual disabilities and underline the importance of respective roles within relationships between people with intellectual disabilities and social care professionals. Conclusion : The partnership between people with intellectual disabilities and professionals seems to be the most effective type of relationship in order to support the self-determination of people with intellectual disabilities. This paper provides a fresh perspective on the role played by people with intellectual disabilities in their relationships with social care professionals. By engaging people with intellectual disabilities as partners in fostering self-determination, social care professionals can encourage social participation and feelings of empowerment. Relationships based on partnership offer people with intellectual disabilities a form of hetero-regulation that can help them overcome challenges to behaving in a fully self-determined way. However, partnership also requires changes in professional practices and attitudes.