The role and future of assessment and treatment units for people with intellectual disabilities is once again the focus of debate and government policy. Reviewing the admissions to inpatient services can provide useful information about the characteristics, needs and clinical outcomes of clients. Data were collected retrospectively for all 36 referrals accepted to an inpatient assessment and treatment unit for people with intellectual disability, between January 2013 and April 2014. Clinical and demographic characteristics of service users were identified through descriptive analysis. Male service users, mild intellectual disability and diagnosis of autistic spectrum disorder were frequent, and a high proportion of admissions had complex and multiple needs. The Health of the Nation Outcome Scale--Intellectual Disabilities was used as a clinical outcome measure. We conclude with recommendations for service development following closure of our inpatient service.