Background: Dedifferentiation refers to the trend of positioning people with intellectual disabilities together with other disabled individuals for political purposes, to act as a counter to differentiated approaches. This article explores the influence of dedifferentiation in professional support settings through the lived experiences of people with intellectual disabilities and their staff. Methods: Ethnographic research, including participant observation and interviews, conducted with an intellectual disability social care provider and an independent community café, both based in an area of England. Results: Tensions exist between dedifferentiation aims and the lived experiences of people with intellectual disabilities, who often struggled to achieve in areas including independent community inclusion and paid employment. Conclusion: Dedifferentiation has disadvantages for people with intellectual disabilities. It can underestimate and mask needs that people experience in relation to their disabilities. Policy and professional support might be improved by (1) recognising these limits and (2) incorporating people's real-world needs into support provision.