A small number of people with intellectual disability (ID) (or learning disability; previously mental retardation) offend or are suspected of having offended. Below average intellectual ability appears to be predictive of future offending behaviour [1] but it is not clear whether those who have a significant ID are over-represented in the criminal justice system (CJS) [2]. Recognising and diagnosing ID in the CJS is notoriously difficult despite screening tools having been developed, such as the Learning Disability Screening Questionnaire (LDSQ) [3].

This chapter describes the development and delivery of hospital inpatient services and community services for those with neurodevelopmental disorders with a focus on services for those with intellectual disability in England. The tired model of service provision is described with Tier 1 to Tier 3 being community-based services and Tier 4 as all types of specialist inpatient services. Within Tier 4 services, there are six categories of services that ranging from high secure to long-term rehabilitation inpatient units or to highly specialised units provided at a national level such as those for autistic people. Autistic patients admitted to forensic in-patient care are a heterogenous group with complex needs. Developing forensic services for people with neurodevelopment disorders requires all relevant stakeholders to be involved using a care pathway-based approach addressing key elements such as the environmentand be person centred so that treatments are tailored to the individual needs of the patient. Future services both in the community and within hospital setting will need to be flexible to meet changing needs and demands.