CPRD GOLD linked Mental Health Dataset (MHDS) is a collection of patient records of individuals who accessed secondary care adult mental health services and who are thought to be suffering from a mental illness. The data include information about the type and location of care received, different episodes of care received within a spell of illness and the events that occurred such as recording of Health of the Nation Outcome Scales (HoNOS) scores, Patient Health Questionnaire (PHQ-9) scores or diagnoses. MHDS data can be used to support research into resource utilisation and provide information about patient access to secondary mental health care services. This can be useful to understand patient pathways and consider associations between primary care and access to and outcomes recorded in secondary mental health care services.