Background: The importance of understanding the needs of older people with intellectual disabilities (IDs) is obvious, but the research available is limited. This study identifies the self-reported needs of older adults with IDs and compares them with staff reported needs regarding the same older adults with ID, therefore specifying and explaining agreements and disagreements. Method: The needs of 96 older adults with IDs were assessed through the Inventory of Identification of Needs (informant and self-report versions). Results: Both older people with IDs and staff reported quite diverse needs related to all the domains assessed by the IIN: physical health, literacy, information, meaningful activity, participation in the community, mental health, basics needs and accommodation. All the mean scores of the informant version of the IIN were higher than the ones of the self-report version. Agreement amongst informants was influenced by the prominence of needs, the accessibility to and the subjectivity of the information, and social desirability. Conclusions: A consumer-driven approach implies that services should be based on the needs identified.