The purpose of this guidance is to support staff in delivering care and treatment to individuals with co occurring mental ill-health and intellectual disabilities (MHID) across all mental health service settings, including inpatient units, community residences and community based services. It promotes a person-centred approach that upholds and protects human rights, ensuring that care is inclusive, responsive and respectful of individual needs. The document provides clear, practical recommendations for everyday practice, grounded in evidence and best practice. By enhancing accessibility, collaboration and effectiveness across services, this guidance aims to strengthen the quality of care and improve outcomes for service users, while also supporting families and professionals involved in their care.