This document provides guidance to practitioners, managers and commissioners on the capacity and provision of specialist child and adolescent mental health services (CAMHS) in England, Ireland, Northern Ireland, Scotland and Wales. Evidence is collated from a number of sources, including published and unpublished literature and examples of best practice. During consultation the document was shared with practitioners, non-statutory organisations, policy makers and commissioners from the agencies of health, social care, education and justice across the five jurisdictions.

The guidance is designed to be a support for service development that is based on assessment of need. It emphasises that local factors should be taken into account, including deprivation indices, the numbers of Black children and those from minority ethnic groups, and whether the area is rural or urban.

For Tier 2/3 CAMHS, an epidemiologically needs-based service for 0- to 16-year-olds requires a minimum of 20 whole-time equivalent (wte) clinicians per 100 000 total population. Teams must have a range of clinical professionals with cognitive, behavioural, psychodynamic, systemic and medical psychiatric skills. Team capacity should be set at 40 new referrals per wte per year. Clinician keyworker case-load should average at 40 cases per wte across the service, varying according to the type of cases held and the other responsibilities of the clinician. Specialist CAMHS work with Tier 1 professionals is best provided by dedicated primary mental health workers working as a team and closely linked to Tier 2/3 CAMHS. Matching demand and capacity is essential to ensure effective service provision.

Recommendations for the remit and staffing of Tier 4 services are given, including specialist community intensive treatment services, day services and inpatient services. It is recommended that 20–40 in-patient CAMHS beds per 1 million total population are required to provide for children and adolescents up to the age of 18 years with severe mental health problems, and that bed occupancy should be 85% to ensure availability of emergency beds.

The authors did not find sufficient evidence to provide recommendations for staffing levels for CAMHS for 16- to 18-year-olds, but argue that significant extra resources are needed to extend services to include this age-group. There was a paucity of evidence on infant mental health services and mental health services for children and adolescents with learning disability, substance misuse and forensic problems. However, the mental health needs of these groups must be met and should be provided by specialist CAMHS.

This document is recommended to anyone who is struggling to answer the questions, ‘what should specialist CAMHS be doing and how many people do they need to do it?’