In this qualitative interview study, we explored the perceptions of adults with intellectual disability regarding interpersonal or social supports needed to express their own self-determination. Specifically, 10 adults, all members of a self-advocacy group, were asked to discuss their understanding of the term self-determination and ways in which support staff have either supported or inhibited their self-determination. Ten themes characterizing supportive and impeding staff actions were identified. The need for greater exploration of environmental and social influences on self-determination is emphasized.